Reddog...big hug to you! I know your pain and I know your being stuck in the ...How could he mode!!! Lots of words that have been posted here that may be hard to handle in this moment of pain, but they are the truths!!!!.
I too have thrown myself back into the fire, and like you and have been burned by the same disgusting behavior as your exabf!
Accept the truths.....he is capable of no better,,,par for course for an addict! Accept the fact that you are now in control of eliminating any more hurts by removing this man from your life...NO CONTACT!
Please, I pray this be your rock bottom...... One that propels you to stop thinking and obsessing about his behavior but rather on how to fix yourself to never allow such a monster back into your life!!!!