Without knowing specifics its hard to say. It's good that he is seeking counseling and you should probably do the same. Unfortunately without knowing what your issues are, its kind of impossible to give advice other than that and maybe check out the single parenting board. You have a baby coming and really that needs to be your priority.
I don't know the whole situation but baby comes first no matter what. Being a single parent isn't the worst thing that could happen to you and truth be told, some people are just better parents doing it alone. My parents literally hated each other but forced it to work for my sake, but in the end we were all miserable and no one was able to be happy until they seperated. They each became better parents to me since they weren't spending their whole time fighting. Good luck with everything!