You see them lurking around your workplace

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Do you always seem to run into the same guy on your way home from work? Where does he leave his car? Is it next to you in the garage or just down the block? It can be a cause for concern if you continue to see the same person in spaces they don't belong in...
They're hanging around your neighborhood spontaneously

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Like the above, you might notice that you've seen the same person lurking the streets around your neighborhood. It's especially strange if you know they don't live there and they never look like they're heading somewhere specific. Be alert for stalkers like these.
They have access to information you never told them

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You might get chatting to someone at the library or supermarket and before you know it you've exchanged numbers and heading on a date. When does it get weird? Right about the time that they start to reel off information about you that they definitely shouldn't know...
They like your old photos on social media

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I mean, we can't say that we all haven't had a quick stalk of someone's Insta, scrolling all the way down to the bottom to see what their first posts looked like. If someone accidentally likes your photo, don't automatically think they're a stalker, but if they do that paired with other signs in the list... well...
Your stalker starts to ask your friends uneasy questions about you

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Your stalker might use those that are close to you to get information that they want or need. For example, they might be very inquisitive about where you live, what job you do, your past relationships, sexual questions etc. If you're friends have warned you about this behavior, run for the hills.
Your family are approached by your stalker

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Much like the above, your stalker might actually use your family to pry the information out, and they might be much more susceptible to this behavior. Parents often love to boast about their kids, and might not see anything wrong with the inappropriate questions.
They've stolen things from you

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Stalkers are weird, and that might meant that they want something of you to keep as a memento. Bear this in mind when your favorite jewelry goes missing, or if you really believe you are being stalked, install some in-home surveillance to help you keep safe.
You think that you're being photographed by them

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There's nothing worse than somebody photographing you when you're asleep... but seeing the photos is like something from hell. If you have that uneasy feeling that you feel like someone is watching you while you sleep, don't always just brush it off. After all, our gut knows.
You're receiving a lot of calls from them (more than usual)

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Stalkers want nothing but to speak to you all the time, whether you want to or not, and this might mean them persistently calling you over and over again just to hear the sound of your voice. Don't let these signs go unnoticed and speak to the police if you feel that someone is stalking you.
They're sending you loads of DMs online

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Another way for stalkers to get in touch with their victims is through social media, which might mean them DMing you, commenting on your posts, tweeting at you. If they are doing it so persistently that you continue to block multiple accounts, consider reporting them to the police.
They've given you inappropriate gifts...

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A stalker might approach you with a gift, or get something sent to your door with creepy letters too. These gifts can vary and are usually inappropriate in multiple ways. For example, it could be something outrageously expensive or it could be something creepy like a lock of your hair.
...and proceed to follow up to make sure you got them

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Once they've had the gift sent direct to you it might be that they continue to chase up afterwards to see if you've received it. They could do this by approaching you in the street, spamming you with messages online or sending creepy notes to your house.
They play the hero by rescuing you from situations

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Have you ever caught yourself in an unexpected disaster and all of a sudden someone happens to be in that exact place waiting to bail you out. For example, you could be caught in the rain and they offer you an umbrella, or your tire has burst and they have a spare on them.
You are being manipulated by them in order to interact with each other

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Have you noticed that your proposed "stalker" has been acting manipulative around you recently. That might be making you feel sorry for them, blackmailing you into doing stuff with them, just so that they can be by your side as long as possible. Make sure to speak to someone if you fear you're being manipulated.
They try to isolate you from your friends and family

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Your stalker wants one thing and one thing only: you. They're not willing to share, so don't be surprised if they start to put a space between you and your friends and family. They want you to feel isolated so that the only person you have is them...
They've seriously threatened you before

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When a stalker becomes desperate they might turn to really serious threats, like the one pictured here. They could be threatening to hurt you (either physically or emotionally), damage your belongings, expose your secrets, any of those things. Speak to the police if you're experiencing serious threats.
They become agitated or violent around you

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Your stalker might not be able to control their emotions around you. Clearly, there must be something going on in their head for them to be unhinged enough to stalk someone, so don't be surprised if they start bursting out into fits of anger and getting physically aggressive with you.
They give you more physical contact than you would like

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Your stalker might want more than just to stalk you and that could be something sexual. Have you noticed that they have started overstepping the boundaries lately and touching you without your consent? If you feel you're being stalked and groomed by someone, talk to the police.
They're always digging into your life

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Stalkers want to know EVERYTHING about you, your life, your family, your friends, your dead dog, that thing you did at the work's Christmas party... that means that they'll be digging as hard as they can, whether it's trying to access medical records, going through your phone, invading your privacy.
You actually catch them spying on you

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What's the one foolproof way you can actually discover a stalker? Catch them in the act. If you've genuinely caught your stalker creeping around corners, in your house when they weren't mean to be, hiding in the back of your car, then that's definitely a cause for concern.
Could your partner be your stalker? Well...

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Could your partner actually be your stalker? Well, if you think so, read on for these specific signs to look out for. Firstly, do they watch you while you sleep? You might not even realize they're doing it, but if you frequently wake up to them watching you... run.
They ask you questions about your whereabouts

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Sometimes, when your stalkery partner is questioning you on your whereabouts earlier that day, it's actually test. They might already know where you've been because they've followed you, but they want to catch you unawares. Be careful what you tell people like this.
They keep pestering you about meeting your family

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This is one of the defining characteristics of a stalker lover. Time is of the essence in all things because it takes time for a connection to develop. But he wants to take things further and meet your parents before you're ready. A stalking lover will research everything there is to know about you and your loved ones.
They blackmail you into carrying on the relationship

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Have you tried to break up with your partner but they have blackmailed you into staying? Well, consider how they managed to do that to you and also what their intentions are. After all, if they got so upset about you splitting even though you'd only seen each other a few months, there must be a reason.
You're punished for not replying to them quickly enough

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He can't comprehend the possibility that you were preoccupied, out of range, or just not paying attention to your phone when he text. Your phone will be flooded with nasty and irrational messages about your completely excusable delay in responding by the time you send him your reply.
They use self-harm as a threat

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One way stalker partners manage to blackmail and manipulate you is using self-harm to get you to stay. It sounds drastic, but they are literally obsessed with you, so losing you will just be too difficult for them to go through. It's usually a last resort for them.
They get extremely jealous of your relationships with others

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A stalker lover is prone to jealous outbursts at the drop of a hat, so you may have to learn to live with them. The relationship-ending insecurity at the root of obsessive jealousy is a lose-lose situation for everyone involved. If you're already guessing they're a stalker, maybe it's time to leave.
They're always asking for proof of your interactions

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Telling your partner something never seems to persuade them. They will demand proof of your whereabouts by either questioning your friends and family or asking to see photos from the location. Don't give into them and consider whether you might be dating a stalker.
You get loads of calls from unknown numbers

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The caller tends to end the conversation as soon as they hear your voice. This is a telltale symptom of a stalker who only wants to make sure you're okay out of love. Delusional stalkers who engage in this and other forms of cyberstalking are more likely to be afflicted with mental illness.
They don't like you leaving their side

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In a social setting they insist on remaining close by your side. If you wander around, they keep a close eye on your whereabouts and who you meet. Even if you're only talking to another guy, he'll get all worked up over it. Not love, but possibly unhealthy fixation.