Wicked, you have told us that your H has a mental disorder but you've not said what it is -- presumably, because he has not stayed in therapy long enough to find out. The behavior you are describing -- acting like a child, lack of impulse control, verbally abusive, inappropriate anger, temper tantrums -- are some of the traits for BPD (Borderline Personality Disorder).
I mention BPD traits because, as a man who lived with a BPDer exW for 15 years, I know that it is impossible to have a calm, rational discussion with a BPDer on any important issue. BPDers (those with strong BPD traits) carry enormous anger from early childhood and that anger is easily triggered, making you feel like you are always walking on eggshells. They also are convinced they are always "a victim," and therefore will blame every misfortune on their spouses. If you would like to read more about what it is like to live with a typical BPDer, I suggest you read my discussion in GTRR's thread. My posts there start at
http://talkaboutmarriage.com/anxiety...tml#post188319. If that discussion rings a bell, I would be glad to try to answer any questions you have or point you to online resources that can. Take care, Wicked.