Separation then divorce but pregnant with my ex's child!

Well I was dating my baby's father from 2011-2013 then split because of him not committing in anyway, our relationship was going nowhere. So thinking I have moved on I ended up married to my now soon to be ex husband of about 3-4 years because I realized my heart was still with my ex and I would be cheating my husband out of love. And that wouldn't be good for either of us. So when we separated in September I ended up pregnant with my ex boyfriends child in late October. I am 22 years old and he will be 23 in May, he still lives with his parents and I live by myself. He is scared to tell them, but he does have a job. But i wonder if it would be wrong to get at least engaged to him. I know next month my husband and I are filing for divorce, so would I be a bad person for trying to be with my child's father??