There is always hope as long as you want there to be. You decide how long to work on it, it's entirely within your control. My W told me she wanted a D and that she would not even consider trying to reconcile. At one point I told her I wanted her to be happy and she looked me in the eyes and said "I don't give a F&*$ what you want!" After seeing something like that, I believe most people would be convinced that it's over. I was able to DB and get back to piecing, and now she's telling me ILY again, so progress is possible!
You should feel good about yourself, you're going through something that is horribly difficult and keeping it together. You are a young, single mother raising your child with no emotional support, and that takes tremendous strength. You are living in your in-laws' house and dealing with their issues and staying sane. Despite all the bad your H has done to you, you continue to fight for him and for your marriage. You are a good person TMC, and you don't deserve to be in this position. No matter what happens, you will be stronger coming out, and will be an amazing role model for your child.
Accuray
Married 18, Together 20, Now Divorced M: 48, W: 50, D: 18, S: 16, D: 12 Bomb Dropped (EA, D): 7/13/11 Start Reconcile: 8/15/11 Bomb Dropped (EA, D): 5/1/2014 (Divorced) In a New Relationship: 3/2015
