I also suggested aand antidepressants for myself..and my husband said the same thing as yours -- that I didn't need them.
In my personal situation I also had trouble opening up about my feelings because I got shut down every time. My husband even went as far as to tell me that I am trying to manipulate him and trying to make him feel bad...when all I was doing was pouring out my heart to him.
Essentially it was ALL about him. Even though he was the one who messed this up to begin with... he was still in a VERY selfish state of mind.
Like I said previously, it took me taking a stand against him for him to realize that I wasn't kidding. I needed this fixed or I needed to leave. That's when he changed.
It takes a lot of patience and work to get through this. Its a lot of heartache every day. I wouldn't wish this kind of pain and drawn own agony on my worst enemy. I haven't reached the end of the road...not even close. But I am certain that time (patience) heals most everything over time.
How much time? I don't know. All I know is things have gotten better for me....and worse at times...but the better out weighs the bad at this point. So I'm getting there. And you can too.
You said there may not be enough left of you guys to build on now. That may be so. I know if there wasn't a child involved, I would not have given him a second chance.
The decision is yours and yours alone.
Follow your heart.