Struggling Relationship.?

So my girlfriend and I live together at my parents house (kill me) and we have a 1 1/2 year old son. We have been slowly falling apart for the last year or so and admittedly, because of me mainly. I've had drug and alcohol problems my whole life and with that comes all kinds of ****. Infidelity, financial ruins all that ****. I've been sober 4 months today and going to AA 3 times a week and its working great for me. But I just cant seem to fix us, through all the **** i've put her through. I just dont know what to do anymore. Its like i cant do anything right, she trusts me ZERO percent. I totally understand why she is the way she is, but HOW DO WE MOVE FORWARD????