i'm clueless....

[Dom R]

I really need to talk with him before the baby gets here. I don't want to deal with this and the new baby at the same time.

Exactly. that's why i'm extra worried about you.
once the baby comes, it will be a disaster if you dont have it all sorted out yet. Because there's no way you will be able to work on it when it comes. However it is just before the baby is born, will be the best it will be for the next X months, most likely, wouldnt you say?

Dont put off until tomorrow, what you can do today.
Be brave. talk to him tonight about it. Dont take "i'm busy" for an answer.
Escalate as appropriate;

First ask him nicely but directly, to talk, "right now", and make it clear to him that "i'm busy" is not an acceptible reply just then, for someone who cares about his marriage.
If he refuses, turn the tv/monitor off.
If he still refuses, pull the plug out.

yes he'll be angry.

recognize, though, that his anger, is merely a tactic to avoid facing you and talking to you. So dont let it distract you.

Dont react to his anger. Stay calm, but firm.


Dont let him turn things around on you. Insist on talking about what HE is doing, and how ignoring you and your family for hours, is not compatible with actually being a part of the family.

PS:

[I keep]
telling him that I'm not going anywhere and that he has time to forgive me and we have time to work this out.

.
no. you really dont.

If you dont get things sorted before the baby comes, then odds are, one or both of you is going to be unhappy enough to call things quits after the stress of the new baby has built up enough.

It may take 2 months. it may take 2 years.
But if it's tough enough to rebuild things with two children now, it's going to be even worse with 3, hmm?