My boyfriend just had a new baby with his ex--- I am scared. Help!?

i know alot of people who have babies with people and dont re kindle there relationship.... many men think that they should...like somehow its there responsibility to make it work.... but its not.. and you shouldnt sacrafice your happiness for someone elses..... he will still get to be apart of the babies life if he wants....if the baby has never been in a home with a mother and a father then the babies not gonna care.... what WOULD hurt the baby is if the father got back together with the mom and then after a few years they broke up or whatever.... its better if he stays out of the womens life..... she doesnt have to be apart of the picture... just the baby does.....