Oh wow, Sue. I would have been very upset too. Regardless of how that "Sue" reacted, your H still made an attempt to pick her up, while out with you. Ultimate disrespect. I wouldn't spend any more time with him. I know he is lost and yes, there is still a chance this marriage could work, but right now is boundary time. If he refuses to stop doing those things in front of you, then don't be 'in front of him'. Don't make anymore plans with him. While D3 is gone, get out, yourself. Go enjoy. See a movie, shop, get a pedicure, all of the above. But for him to over-drink and hit on women while out with his wife? What would you tell a friend/family member if their husband did that to them. I just know how much it hurt you, and I don't want you hurt.
HUGS
PS: I giggled about the 'too complex for a therapist" comment too..... My H I am sure thinks the same way....