Frank, I had the same feelings about my H. I thought him a coward, and a fool for allowing himself to emotionally leave our R. He betrayed me, he communicated more with OW, living in a fantasy world where they hadn't even seen each other since they were teens, and now suddenly they had always loved each other. They only spoke on the phone, and via email and IM, but this was apparently what he felt was his road to happiness - screw his M of almost 20 years, and his children. Believe me, I understand completely how you feel.
He accused me of so many things - some completely false, and some I thought rather silly, but they need something to justify their actions. What worked for me, was having patience and deciding that I loved him unconditionally. Which doesn't mean he got to do what he liked. I had my boundaries.
Anyway, we are in a committed R now. He is trying to earn my trust back (my biggest issue now), does all kinds of things. It is good to vent your anger and frustration here on the bb - helped me a lot. Your feelings do not make you a bad person - if you didn't feel this way sometimes, you wouldn't be a normal, betrayed spouse. These feelings will definitely help you detach. Once I detached, and was actually looking forward to the D, and being in charge of my own life, my H suddenly found that he still loved me, blah, blah.
I remember how he also thought that I didn't appreciate how hard he worked, but I never got any words of appreciation for also working to earn money for the family, or working to maintain our home, and be a mother to our children. Oh! But, he felt the OW was a good mother - my @ss, she was willing to put their lives on the line for all this BS, whereas, I had never even considered having an A, even during times when he was putting me through absolute hell (other than the EA this time). I felt, this was what one gets when you are faithful, and supportive. Ha! So, now I have no expectations, and it seems to work.
Sorry if this post seems all over the place. I just felt I needed to respond to your post, but I am also in the middle of getting assignments done, and don't usually have time to do any posting - just lurk most days. Take care of yourself - be your own best friend.
Me:57 H:52 M:28 Got another lawyer last year and filed. D35,S/D twins28,D22 EA4/04 End? Who knows? "Life is like a mirror. Smile at it and it smiles back at you." — Peace Pilgrim