We have all backslid...the last time I did was right before Christmas...I learned to never ask about R unless you are ready to hear the worst things you can imagine (and then some you couldn't)...I feel for you.
Did you write down all his "complaints"? I found for me it was useful to objectively go through them one at a time, and written down I could remember exactly what W said...many of my faults were valid without question, others I was clueless about, yet others were behaviors or ways of interacting that served me pretty well in my career/job, but at home and in my R with W and kids? Not so much.
Throw the list, and your thoughts on each bullet point, up here, I am sure we could help sift through things.
As far as his dating...yes, that hurts...the time and money...I have ended up financing her "explorations" and the equipment to do so since she is a SAHM. It s_cks, I know we would rather they spend that time and money on fixing the M...
Hang in there!
T^2
In the depths of winter, I finally learned that within me there lay an invincible summer. - Albert Camus
Uncertainty is the very condition which impels people to unfold their powers.-Eric Fromm