I"m so sorry to hear all of this, all though you're getting good support here
He sprung on me that he doesn't love me and is leaving me soon.
In my experience, these words are also uttered by someone have an affair, all though with an A, the affair is always first and foremost with alcohol. That takes priority over anything else in their life.
L2L mentioned that folks will swap out one obsession for another and that's so true. Whether its AA, his own narcissistic recovery or whatever.
I really like that you acknowledge your life and your kids lives, will be better off without him. Hold to that truth.
And the others have all the right answers about how to cope with anger. There are healthy ways of working through these stages, and how knows? You may find amazing peace and a wonderful new life waiting for you after you've worked through it. With that loser gone, it's almost a gar-un-tee...