Husband cannot admit guilt?

My husband will not admit his wrong doings. In situations when he's overreacted or said something that crosses the line, he turns it around while and states everything that the other person did wrong that ld him to act the way he did. When asked if he believes he's said anything hurtful or rude he will simply say no because of "the circumstances". He's always saying that "everything is circumstancial" but I don't even know what that means. Me and his mother have asked him to go to a therapist and he tells us that because I have mental problems (sever ADHD and his mother suffers from depression) we want him to seem crazy too. Am I just insane? Is there some sort of classification for these reactions? How can I talk to him without getting an angry reaction?