Hi Sherry, welcome to the forum. Basically his approach has a lot to do with those he actually feels comfortable with, compared to those he does not. A stranger he is not comfortable with, hence he will present a mask of himself, the person he wants to be, or be seen as, but not his true reflection of his current mental self. To you, your family, the people he loves and is comfortable with, he is himself, the mentally messed man that is struggling to live day to day, and at times you certainly wouldn't recognise. With that comes guilt, his guilt, a guilt of the way he treats those he loves yet doesn't understand why he does it. He does it because he is comfortable with you all, loves you all, but doesn't understand the impact, and when he does, then feels guilty about it. Revolving door basically.... or a cycle for a better term.

I'm sure you've heard the term, "to break the cycle" or "break a link in the chain"... same thing.