I started a new job last year and my female co-worker and I became friends quickly. Then, all of a sudden, she is bad mouthing me to other co-workers, my boss, and anyone who will listen. She constantly monitors everything I do, looking for mistakes. Now I am moving to another area, and I just heard today that she has been campaigning against me over there too! One final note, she likes to tell people lies about me to make others think I am some kind of "shady" person. I never did a damn thing to her! I thought she and I were friends, but now I think it was all an act to manipulate me. I feel like such a fool!
Is it normal for a female coworker to constantly bully you? She seems so obsessed with me, and I fear a bit for my safety.
Is it normal for a female coworker to constantly bully you? She seems so obsessed with me, and I fear a bit for my safety.

I feel your pain. The fat office skank with no life is the bane of my existence.
What you do is go to whoever's in charge of HR or whatever and tell them that she seems mentally unstable. When whoever you tell asks you why, tell them that she's become obsessed with you and, you know... what with all the workplace shootings in the news and all...
You catch my drift, and in reality, you're only looking out for yourself (because really, you have no way of knowing whether or not this chick has, like, a satanic shrine to you in her bedroom or something creepy like that).
Trust me, if you frame it right for your boss or the HR person, she'll be fired before the end of the week. Not only does your company not want to have a creepy person around, they don't want to get sued if anything *does* happen, and you telling them about it now means they would have known ahead of time should something like that happen.
And if you have any moral issues with tanking the office lard-tub, think of it this way - You're doing the rest of us a favor. The more of those fat, useless, stupid, ugly office bitches we can get rid of, the more jobs there are for useful, kind, clean, self-esteem having women like us.
Burn that fucking bitch to the ground!
maybe it's time to talk to your boss again. start documenting things just in case.
Unless you are otherwise quite enjoying your job, look elsewhere. I agree with the point that you don't (generally) make friends at work.
I changed jobs and a girl who tried to act like a friend but gave me hebie jebies (did not trust) has become obsessed with me. To the point that she hooked up with a lady where the new job is who is 50 yrs old and the two peas in a pod began to play games together - that began over a year ago and is still going on. Only now they have a bully on their team. The girl wrote letters bad mouthing me - problem is that what she stated was true about her, not me. She was having affairs with two guys; one at work and one by the beach some where plus she was living with a guy whom she finally married after 12 years of living with him. She has violated HIPPA several times over. Is jelous of everyone she works around and tries to get them fired because she thinks she should have his/her job and make the money that he/she makes. Of course everyone likes to believe the worst so they all think I am this horrible person.
To boot - two of the women who are currenly work with me are in their 50's and are Supervisors in the department. I am not a super but report directly to the Manager. He is fully aware of their behaviors but is not strong enough to stand up to the bully and the maligner. They operate him like a puppet - tho he will not rid me but he does not do right by me either. Anytime he gives me a duty, the maligner pitches a fit until he gives it to her and if he does not, the bully bullies him until he does.
These two pull something at least twice a month and have gotten away with it for over a year! I am a wreck tho I refuse to show it to them. I feel like I work in Hxll. Anytime the maligner goes by the office door, she must stop and stare. When in a meeting, she spends the meeting staring at me. The Maligner is obsessed with me to the point of discomfort and at times it scares me as there is wonderment as to how far these nuts will go.
Here is the ironic part....this position is in a large well-known hospital. One would tend to think the mental illnesses would be under control. NOT!
That is key when and if things go south.
she used to complain all the time to the boss and bitch about me to all the people here and they all used to tell me about it. i was always professional with her and in the end i got so tired of it, i picked on everything she did wrong and i sat right next to her and made her fix her mistakes as soon as i found them. she eventually quit which actually made everyone here happy that she was leaving. some people are just mean spirited and jealous and they think its okay to treat you like crap because of it.
this may sound petty but when i was really nice to her, it made her more angry so i tried to make her look like the nastiest person ever by being nice to her face in front of everyone and then she would make up some bs story that i was mean to her and everyone knew she was lying. i never actually bitched about her to anyone at work which made her look even worse.
ask her politely to stop bad-mouthing you because it makes you feel uncomfortable. then when she does it again, make a formal complaint in writing to your boss and if that doesnt change anything, go to your bosses boss etc. if that doesnt change anything then you should find another job where they actually care about their workers. its not worth working for a place like that because you will constantly be stressed and make more mistakes and you might even get the sack.