Single mom going through a divorce/custody battle and struggling emotionally

Anyone out there to give tips. Or their stories. Or any positivity. Im due with baby #3 we have 2 other children and im going through a divorce with my emotional abuser. Im in so much pain for my children and just what hes doing that is making this as hard as possible. I am losing sleep at night worrying about things. Its so hard to see the positive. Im trying my best to not show my emotions around our children but I notice at times my frustration comes out on them. I am feeling guilty for not being a better mom. Or allowing the abuse to get to this point. I hate seeing my 4 yr old cry. This is so hard. When will it get better.