W.W.
My husband is going through the same type of thing... kinda. We've been TTC for a while and I was just diagnosed with PCOS and the doctor put me on meds that should help us conceive within a few months. As soon as I went on the meds, my husband suddenly said he didn't want a baby right now.
Instead of depression, he is letting nerves take over his life. And just like your husband, mine refuses to talk to a doctor about it. I finally got him to agree to a counselor because I told him he was making me miserable. I didn't say it harshly or angrily... I broke down and started crying one night because of the way he's been acting. The sudden "stage fright" to conceive has left him crabby, rude, and stressed out. And he takes it all out on me.
Maybe suggest going to a counselor? Sit down with him, one-on-one, and be calm and quiet. Don't yell or scream, be real with him. When he sees how upset he is making you, he should be more apt to agree to at least talk about it.
Just like my husband saying that he "doesn't want a baby right now", even though we've been TTC for a year and I know he wants a baby, he used that as a shield for what's really bothering him - he's nervous he's not going to be a good daddy. Same thing with your husband. My guess is, something else is eating at him.
I hate saying "give him space" or "give him time" because I hate the way I felt when my husband was acting this way, but just try backing off and stop offering ways to "help" - because he is a man, and men don't think there's something "wrong" and that they don't need "help", when everyone else can clearly see he does.
Good luck to you.