She honestly sounds fucking crazy, and I know from personal experience that being in a relationship with someone who's crazy will make YOU crazy too. Stay the hell away from her. You know she's not really pregnant, so anything else she says is HER problem. Even if she says she's going to kill herself. Her actions are her choice, not yours.

I'm sure you'll find after enough time away from her that your emotions will level out again and you'll probably wonder what the hell you were thinking for letting it go on for so long. A chaotic relationship evokes a lot of emotions and even though it's bad, a person can get addicted to the chaos.

I second reading up on emotionally abusive relationships, and when you're over your feelings about the relationship, work on what was up with you that made you allow this for so long in the first place.