An ex-flatmate stole pictures from my facebook (which friends only then and has now been deleted.) profile and started using them as her own and contacting men and women, sometimes even asking for money and presents from them.
I found out when one of the jilted girlfriends of one of the guys she was talking to found my profile and sent me, what could only be described as an essay on what a filthy disgusting whore I was, and how I ruined her life. I thought it was just an insane message from a crazy stranger, blocked them and went on with my life.
Several months later I get a message from someone else asking me to stop messaging their partner. This time I asked for proof that I'd been messaging them and they gave a link to the fake profile and some screenshots of messages.
I then proceeded to freak the fuck out, because there was someone out there using my pictures and pretending to be me and fucking with peoples lives, begging them to give her money, and talking dirty to them as me. I don't actually think I can fully put into words how scared/disgusted/angry I was that someone would do this. I figured out who it was because of the way they talked and things they liked, and a picture that she uploaded onto her real facebook.
When I confronted her about it she reluctantly admitted it and told me that it was my fault because people like me are treated better than people like her, and people like her deserve to have my life, because people like me don't deserve it. She was always a bit quirky but I was genuinely frightened and it was clear that she was enjoying her handy work. The police also did sweet fuck all to help.
I moved out as soon as I could, but not before she cornered my partner and tried to convince him that I was emotionally abusing him and cheating and that he should leave me for her. She told him that he would learn to love secondlife and she could teach him how to get disability benefits too and they could become one in a world where I didn't exist.
I could include many other stories of living there but that would turn this wall of text into a full on novel.
When my partner and I moved we received both received a very long, rambling bizarre e-mail, (supposedly) from her sister saying that we fucked her over by leaving. It was our fault that she was going to start self-harming again. That people with Borderline personality disorder only do things like that because they like you and want to be your friend.. Instead of replying we informed police and blocked her.
I refuse to use facebook/twitter/google+ or anything like that years later, neither does my partner.