Thanks to the poster who linked your other thread.
I can understand that with a new baby so imminent, you just want it all to come right, but it won't will it?
I think he's seeing someone else, but whoever she is is not free to live with him right now, hence he's in no hurry to leave the marital home. I know that must be heart-breaking and the 'not knowing' must be killing you, but I think the decision you've made is a bad one.
Once someone has 'checked out' of a marriage like this, it really is best to separate because it's much more painful trying to get someone to love you again, mainly because it never ever works. He's actually very cruel saying 'the feelings might come back' because that gives you false hope.
When someone is having an affair, usually the only time the feelings come back is when it has been discovered and the cheater suddenly realises what he stands to lose, especially if he thinks (and is being told) that he has lost his marriage for good. The person in your position has to decide at that point whether to attempt reconciliation and forgiveness.
In the absence of proof though, the best thing to do in this situation is to explain that you can't stay in a marriage with someone who feels so little for you - and to let him go. He's actually not ready to live on his own right now, but it would do him good - and he needs to get used to life as a single parent. Asking to remain in the family home is unreasonable and are for self-serving reasons only - it's certainly not for your benefit at all.
I don't think he wants to be seen as the guy who walked out on his wife when she was about to give birth, but he has walked out of the marriage hasn't he?