Do you have family support? Right now you have to focus on you and your children. Hubby sounds like he may be in a MLC. Go to the MLC part of the forum and read there.
If it is a MLC you have no choice but to detach and try and GAL. His behaviour is immature and Narrsistic. This could go on for years.
I had a friend who's hubby wanted a divorce while she was pregnant too. He's still making a mess of his life. She went on to become a nurse, remarry and recently gave birth to a baby girl. Best of all she's happy.
Me 52 H 44 T9 M 5 BD 12/11 H split 8/12 OW moved in 12/12 OW gone for good 6/14 We get closer again 9/14 SD 13 Me 4 Grown
Accept what is...let go of what was and have faith in what will be.