If you were me what would you do? Girls please help me!!!!?

Hey guys. Me and my girlfriend have been dating for almost a year. We really like each other but she is going through a lot of pive emotional distress. (fighting with mother, jealousy issues, deceiving a little, lying about how she feels, not talking to me about her problems, and almost like spying on me). I have been with her through a lot of stuff and I've been next to her helping her with everything and giving her almost perfect advice. I have never cheated on this girl, I have never even thought about it, I do not flirt, I hardly check out other women, and I constantly display my devotion to her and do sweet things. Every time she thinks I'm lying I'm not and I never am in all honesty and I always prove that I'm telling the truth. I love her dearly and she loves me, but she trust nobody and every time she accuses me of stuff I have to take the initiative to make things right and its getting old. How do you think I can gain a little trust because i feel like I've tried EVERYTHING!! Please help!! I guess i just really want to know if its worth it or if i should just leave her. This could be the relationship of a lifetime because when things are okay, i am happier then i have ever been in my life...