Oh, am I familiar with resentment that builds ... it drives a huge wedge in any relationship. My H and I had plenty of it.
It sounds like you have been so strong in your M. You've been the pillar. You've certainly hung in there through a lot of adversity! That takes a lot tenacity.
I wonder if that has had a negative effect on your H? He sees how strong you are, but he is not. His A may have been an attempt to find someone to boost his self-esteem. Not that you did anything to drive him to it, but because of his problems. He sounds like a lost soul. How is he doing with his depression? Is he seeking any help (i.e. counseling)?
How is your weekend going? Are you still getting the silent treatment?