UPDATE My therapist says I need to have a long talk with him and see what he wants to do about the marriage. I’m not sure if that’s what I should do or not.
We typically don't encourage relationship talks because they never seem to go the way the LBS thinks they will. Things seem better and the LBS brings up a R talk and the WW spouse pretty much gut punches them and says "nothing has changed". This then sends the LBS cycling again.
If you are ready for the "are you in or out of the marriage talk" and are prepared to ask him to leave, move out or file for divorce if you don't get the answer you are looking for then do it.
If not, which I don't think you are, just keep doing what your'e doing. Detach, GAL and work on yourself.
Again you are in a marathon and probably have run a quarter of a mile of the 26 miles race. This takes infinite patience.
