I can't figure her out

So I been dating this girl for 2 years, we have had a child together and what not. In the time I have recently found out about all sorts of lies she has told me, they are small but makes no sense as to why she told them. She answers every question with I don't know when she is in a corner about something she has done. Her family and friends hate me because she gets mad and makes me sound like I'm the worse guy on the planet. One minute she loves me the next she is confused. She keeps my son away from me, that one probably hurts the most of them all. We can;t ever discuss anything she has to scream and rant and never stays on topic about what we are talking about. She stays jealous, yet feels the need to talk about how cute other guys are in front of me. She refuses to stand up for herself, as of right now she is about to be 24 and is afraid to tell her mother she is dating me. She can not form her own opinion. She pretends that all problems can be solved by avoiding them and never talking about it or doing anything about them. She says I'm nit picking at her. I might be, but she has me on a mental roller coaster. What is going on here. Is it because she grew up with a emotionally unstable mother? Is she acting as a product of her? I can't stand this crap much longer to be honest. She has no moral value's or something, I don't get it.

I think you should just go with the flow and accept anything that happens. If she doesn't want to tell her mom about you two quite yet, then don't rush her. Don't blow up at her either, that gives her a reason to say your a bad guy.