Hi Lost,
its the usual saga, isnt it? Denial, lies, violence (when he thinks he has lost power), then sorrow and trying to make you pity him afterwards.
It is the hard cop, soft cop technique and that is why it is so hard.
I truly believe that you should not go on this holiday, it will undo so much, and you will be back where you started. You can see yourself that you are vulnerable to being partly won over, and he has given you nothing that you need so far of his own free will.
It will not help the kids- if you are convinced it will, take your mum instrad or go on your own, or have a different trip and make it sound fun to them.
He is credible and believable, and the reason you let him do this is because you see sense and see that he does not calculate each step on purpose, he is in pain himself, so you feel sorry for him.
But he is the cause of your pain, isnt he? Only he can take responsibility for his, and he will not- he is an ostich. And he wont whilst with you, like this.
Take control of your life and deal with your own pain, and its causes- him and his behaviour.
You cannot change him, and trying to control him (which wont work anyway) will not bring you relief.
That is the way to look at it, in the interests of the kids. (by which I mean, by the way, the under 16 variety, not him!)