Hi, welcome to the forum and congratulations for seeking help!
I did a ptsd program with my partner and in the partners session we were told one very important message- PTSD IS NOT AN EXCUSE FOR BAD BEHAVIOUR!!! Yes PTSD is a terrible illness with no cure and all of that but honestly, no one deserves to be treated as you have explained. His leaving you when you were grieving was extremely in my opinion however he may have left because death is a stressor to his ptsd. It still doesn't make us feel any better to know that though, does it? What I believe you need to do, is mark in a diary or journal or even on a calender when he is having a good day and when he is having a bad day and how exactly you fit in to all of that. Give yourself a specific time frame to do this for, say a couple of months or so. At the end of those months, make up a tally. If he upset you or hurt you or whatever on more occassions than he was nice to you, then you should seriously consider your happiness away form him. I know how hard it would be to walk away, especially with the added threat of violence; however sometimes we have to put ourselves and our happiness and well being first. I personally don't think I could/ would tolerate this behaviour at all.
Anyway, we are all here for you to chat to, even if you do just want to vent about life in general. As is said often here "we are all in the same boat"!
I hope things get better for you,
Tammy