Dooin, sweetheart, please, please do not swallow this baloney whole.
"He knew I was unhappy and things were bad but he didn't know how unhappy or bad or for how long it been had going on. He accepts that the way he has treat me lately is not right. But to be fair to him I give as much as I get.
He thinks that because you shout back you are not affected?"
He thought because you shout back it was not affecting you?
If you were silent then he would tell you that because you were silent if was all water off a duck's back.
If you cried then he would accuse you of being a manipulative cow.
The important thing he said was that he forgets everything after a while. He has not accepted that what he says and does are the things that are wrong and must change. You are living with someone who expects you to judge him on his intentions and not his words and actions and who expects you to be just like him as far as how you feel is concerned. He has not accepted any responsibility here.
He has instead tried very successfully to dump the blame on you for the way things have gone on. There is nothing in what you posted to indicate that he is taking any responsibility for himself. He won't even lose weight without you there; horning in on your exercising is another way of making sure other men are not looking at you of course. And if he fails to lose weight then he will blame you for not being supportive enough. You will not win here. He is determined to have things all his way.
Please read Chipping's post again:
'A man who throws his dinner across the sitting room because a child asks for a bit of his fish is not going to suddenly turn into partner or father of the year because you have talked (yet again). You have told him before, it's just this time he's pretending to listen. You have already tried for the children, for a bloody long time. What is making you too scared to leave?'
She is dead right. Really, what sort of a moron needs to have simple things like that spelled out? What sort of an idiot does he think you are to try to say he didn't realise how you felt or how the children must feel?
I don't want to depress you, but a man like you have there needs to commit to intense therapy to deal with his sense of entitlement.