Couples Counseling

Has anyone had success with couples therapy?  My ADHD spouse thinks the marriage is "not meeting his needs" and wants a divorce. He admits to having ADHD but he refuses to explore how it has impacted our relationship. He sees how it affects his work but does not see that it has changed the whole dynamic of our relationship. (I've become his mother in a way, his porn addiction, his need for stimulation, his need to flirt) He has been to some therapy on his own and has been off and on ADHD and depression meds over the course of the year.  I found a therapist who specializes in couples work and ADHD. After meeting with her once on my own, she suggested bringing him in.  The appointment is next Monday but I have not yet asked him.  I am scared to!  In the past, he has come around a little when we went together, but then he would accuse me and the therapist of ganging up on him when we got home. I know I cannot "fix him" but I am fighting for this marriage and I have to do what I can.  Any insight?? Any ideas on how I can approach him with the invitation?