There is always drama in my life now that I'm with her. She was only 19 when we started dating. She is now almost 22. I'm 29. She moved in quick due to drama with an employer/roommate. Her parents are very strick so I had her move in with me to help her out. We got along great and we decided to keep living together. The problems started quickly. She always talks crap on people and she thinks they are doing the same. I guess she has very low self esteem and a bit of a chip on her shoulder. She has ruined many friendships that I've had. Most of them with girls who are friends. I've been able to keep a couple of them because she got along with them. She's had problems with someone at almost every job that she had. It seems like she is mellowing out but I can hardley stand it anymore. now she's talking smack on my cousin. Yes my cousin might be a ditz but I don't want to hear it. It's constant drama. Things that seem insignificant turn into major drama. She also feels the need to get back at people who she feels have wronged her. She calls it sticking up for herself. I call it being confrontational but maybe I'm too mellow. I love her but I'm drained. I'm the type of guy who doesn't get involved in any drama. i never have issues with anyone.

Depending on how strong your love for this girl is, you need to pick a day to sort it out with your girlfriend.
A serious converstation, a one-sentence warning doesn't have any effect.
Fact is, she's 22 and immature and has a lot of growing up to do; growing up that you've already done. If you love her, be honest with her and tell her she's going to have to grow up a bit if this is going to work. If she can't face up to her flaws, you'll probably have to move on eventually.
Even if she tones it down and grows up a bit - you may find yourself trying to fit a square peg into a round hole. So longer term, you may want to look at your options.
At the very least, I don't think you should be rescuing her from herself. You can tell her how you feel. But it is up to her what she wants to and can change.
She has a lot of growing up to do, and you shouldn't waste your life waiting for her to do so.
Go and find someone you enjoy being around, and don't waste any more time being miserable.
Good luck.