Don't let negative experiences change you since you have a good heart. Many opportunistic people, men and women, tend to take advantage of that, unfortunately.

I know as I was like you before (except that I never did cry that easily). But I always helped people and many did take advantage. But I'm older now and more jaded. You will probably learn, as I have, to discern things better and stop being a doormat.

You have many friends - wonderful! Keep it up but be careful that your being nice to the world is not simply to have many friends, to gain the approval of others. You'll find that fewer but very good friends are better than having many friends.

Re: your situation - what can you do?

"the first time i saw her i have a bad feeling for her that she is not nice" - always trust your instinct. Be cautious if your instinct tells you something's wrong. It usually is. I don't mean judge immediately and cut people off. No, just be wary, that's all.Time will tell if your 1st impressions are correct or not.

You were kind to see the best in the person first, which is excellent. But there has to be a limit. After that limit is reached, you ought to take action. What you did was correct so be strong and stand your ground. Some people are not worth your friendship.It's ok not to be friends with everyone. Your self-esteem does not depend on having many friends. Like the saying goes, you win some, you lose some. No big deal.

The fact that she was thoughtless "she dont care talking at her mobile with her bf at 1am-3am in the morning,i cant sleep" - itself shows her thoughtlessness and egocentricity. The world does not revolve around her. Yes, we have freedom to do as we please but her freedom ends where your liberty begins. If she's disturbing you, you have a right to tell her to tone down.

It's a public nuisance esp. after midnight - where most people are in la la land. You should approach her calmly (not when you're angry cos then you'd be emotional and then it can get ugly), tell her that it's not acceptable to be disturbing you, etc. But be prepared for her to be offended. Stay calm and rational and say your piece. If she doesn't accept, tell her again at another time but this time, preferably bring a witness along, that would be helpful as 2 people can corroborate / support your side of the story. She's most likely going to lie and twist things around. So be prepared. If she still doesn't bother, then tell her to move out. Let's see her rent an accommodation without busting her budget in Doha.

Re: the attempt to look good by her in front of your office mates - talk to her privately first about you not being happy about her bluffing as it reflects badly on you. If she insists that you're the one lying, then like I said before - 2nd time, bring a witness along.

Reason I say is this - 1st time, talk privately to her to protect her ego. One on one. If she doesn't want to listen, then bring a witness. Good luck.

/If I were you, I'd just fire / scold her and tell her to get out ... but that's just me, at 90 years old.