Have you read about the pursuit and distance dynamic? Were you ever pursued by someone you didn't like? The more they pursue, the less you want to spend time with them, until, if they don't stop, you become repulsed by them.
Not pursuing allows him to let his defenses down and enjoy your relationship a little bit on his terms. If he feels like engaging with you will lead to you asking him for more, he's less likely to engage at all.
On my first appointment with my counselor, I said, "My husband is going to divorce me, and I want to get through this without hating myself."
She helped me process things, and helped me feel like a worthwhile and lovable person while I was learning to self-validate. She also helped me break mental habits that lead to a lot of presumptive worry and stress.
And like I said, I think you could use a sounding board to decide if you want to be married to your husband as he is, or only if he stops being depressed and wants kids.
Me: 44 H: 44 Kids: 20, 16, 16, and 10 Together/Married: 22 years H announced he was emotionally detached and considering D: 4/4/16 H announced he is going to try to stay and reconnect: 5/1/16