You know him better than I do and I think you make some valid points. But I still think it has something to do with the stage of the marriage that you are at. In the beginning everything is new and rosy so that might have helped his depression and there is stage where you also have to adjust to one another but then eventually you adjust and settle in for the long haul and as a lot of people have happen in this forum, after many years of things going well suddenly something snaps. But it sounds like he reached the point where one normally adjusts and as you point out, he feels it might be too much for him. When you have a long history behind you at least you know from experience that somewhere deep inside is a person who is capable of handling your marriage and family life, even if they are going through a phase where they want to run away, at least there is something that they might go back to.
That's what makes your situation so difficult, because it sounds like you don't have a long history of living with him and the children and having stability. BD was only 8 months after your first child was born. Maybe he really can handle the situation if he sticks it out, but this is a man in a totally new situation and his first reaction seems to be that he doesn't believe he can. And that's the risk you face, you just don't know either because you don't have that history with him.
