He must be wondering if it was all worth it.
• Marriage over
• Parents not keen on you.
• Lost friends
• Probably talked about at work.
Add to all that he was expecting some extra marital fun sex... not to have attention taken away from him and on a baby.
It takes away the opportunity to be spontaneous and do those care free things you do in the early stages of a relationship.
He must be kicking himself for not using protection...because if he leaves you, that's 2x2 and child support to add.
Chances are he does regret it, but his Ex won't have him back. If he leaves you, then that's the potential of a third child with someone else. It'll be a big dilemma for him. On the one hand a new partner would probably be accepted bu his friends and family....but that comes with other issues.
Most women want a child...so he's either got to find one who doesn't or who has her own already. Then hell think...what's the point in living with someone else's kids and not his own... so he sticks with you and his child. It's better than the other options for now.
His current position is likely to accept he fucd up and he feel his misery is if his own making. Kind of 'you made your bed, so lie in it'
He agrees to what his wife asks because he respects her... many ex husbands have no regard for their Ex. In addition he probably carries a lot of guilt.
Does his DD see your child much?
I don't see this lasting long term, because of your starting point. You will always be a reminder of what he did and there could be inner resentment with the alleged accidental pregnancy.
When your sleeping with someone else's husband, double and triple protection should have been a priority for both of you