I am not, but I am sorry to hear that you are. Honestly, if the relationship isn't working out then its not working out. Your kid will be much better off with parents that live separately and are happy. Staying together for the kids is not always the answer.
Coming from a broken home, I'd even go as far as saying sometimes staying together makes it worse for the kids.
Do what is best for you and your baby health wise. Don't stay out of "obligation"