I don't suggest anyone getting to this point. If a situation is so bad that you want to withdraw from it, get out of it. When it's time to throw in the towel is when you realize you've done all you can. You tried your hardest to make it work and it's just not. When there isn't even the faintest glimmer of light at the end of the tunnel, when you feel like there isn't an ounce of hope left, that's when you throw in the towel.
Now, on to my present situation. Your spoke about harboring anger and resentment towards your husband, and I'm in sort of a similar place right now. My current husband and I are trying to build a new life surrounded by our children from our previous marriages. I can't begin to tell you how difficult that is. We do nothing but argue over the kids, and resentment is building in both of us, I think. We're going to counseling next week and I hope we can get some of these issues between us worked out.
As for where you are right now, it might be a good idea for the two of you to completely start over in your relationship. You need to take your past and destroy it, and start building a new chapter in your marriage. It could be something symbolic like writing down all your resentments and then the two of you burning the paper as a symbol of letting go. Or you could each right down your resentments and exchange them and each of your is responsible for working to eliminate the other's resentments. However you do it, I think your relationship sounds salvagable. I think you've just gotten to an plateau of anger you can't get off of. And that's sort of where I'm at right now, but I want to get off of it. Unlike my first marriage, I think this one I have now is worth saving. There is still a glimmer of light at the end of the tunnel.
I wish you the best. I hope both of us can overcome our resentments and move on. (((HUGS)))