I know exactly what you mean. It is so tiresome to try and hold a marriage together with a WS who is really not 100% invested in fixing himself and the damage he has done to the marriage. I have heard on SI that it is not truely R if they are not doing everything they should be doing. I have also heard that the A is often not what causes a D, but the continued actions of the WS. I find myself detaching daily from WH#2. He doesn't get the pain that this has caused me and continues to cause me, even though I have voiced it to him on numerous occasions and after numerous DDay's. I know I have to detach from him in order to get myself to a point that I can move on with my life. I also know that I don't want a D, but I know that eventually he will stray again to get his ego-kibbles and I will have no choice this time but to D him.
I hope your WS begins to step up and do what he needs to do to help you heal, but usually if they haven't already they are not going to. It is too much work to fix what is broken in them, so they just choose not to deal with it and think it will just go away. It doesn't and then they usually stray again when the BS won't just "let it go". As the saying goes, you will leave when you are sick and tired of being sick and tired.