I see the light after 4 years of untrust is it too late?

I started dating a girl. the first week she told me "I have cheated on every boyfriend i ever had". well that planted a seed in my mind..it grew into depression and then paranoia about her cheating on me..i have always had trust issues my whole life and that didn't help. i caught her talking to somebody secretly one night. I confronted her and we talked all night about how she thought we were over and she was sry and was to go to him the next day and stop it....well she came back to me the next day and gave me an elaborate well detailed story of how she told him off and his reaction etc. this was all untrue she admitted later never really giving me an answer to why.but the shear blatant way she can lie and manipulate people was scary, she even went as far as telling me she has always been able to convince anybody of anything she wanted.....a clear deal breaker for me...well for years now she has told me she grew up and is no longer that girl anymore I have realized after all the paranoid episodes we have had over this and me trying to catch her cheating...she wouldn't put up with that if she didn't love me...so recently I had been so sure she was lying to me that I nearly ruined my school attendance trying to catch her in the act....I have lived for years with her, slowly putting myself in a shell. numbing myself with weed and video games....after this last paranoia spell something clicked inside of me...I believe maybe divine intervention??? I dunno... but I feel like a ton of weight has been lifted off of me, I finally trust her for the first time in my life and it feels so good inside...different than anything else ive felt with her ever...I know the man I want to be for her and, if she has dealt with me for so long she must love me right??? I finally feel confident with my trust for her and have gotten rid of her only complaint about me....the "emotional roller coaster" being paranoid finding nothing then her explaining it away in a way that makes sense to me....well I see the light, signs whatever you want to call it.......but she is soooooo jaded and angry with me since I have realized this...all she says is oh im sry I cant just snap out of it just because you have realized im not cheating....well it has been 2 months almost and the more calm and happy I get, the more down and hateful she gets towards me...have I waited too long??? and if so why put me through hell for bettering us, myself and our family...its getting so bad she is accusing me of everything I used to say to her....we have a three year old and its to the point where I cant engage in everyday conversation without her cutting me off and cutting me down....she says it isn't hate she just needs time...but the more time passes the more I feel no more love from her.....would a woman like that have the courage to stick by me all this time, but none to say its too late and its over??? or is she just punishing me before she leaves...either way it is effecting our son badly...she gets three words into a sentence and he screams knowing she is about to have another meltdown....I don't even raise my voice to her anymore...just waiting for her to love me again but im at the end of my rope....im a good man with no more issues that needs his woman back..undamaged will it happen???