Hen.....you ask us what is going on in his head. No one, here, can do that. In fact, there is no one who can know exactly what is going on in some other person's mind.
Lol...if you ever do find someone who can tell you what is going on in another person's head----please notify us, because that will become International News....lol.
The best that any of us can do is to make an "educated guess" based on the totality of their actions.
Your guy's actions, based on what you have shared, say this----typical, predictable alcoholic behavior. His behavior follows the same story that y ou will see written on the thousands----yes, thousands----of stories on this forum. Almost word for word.
Many of the other posters have posted some of those behaviors for you. It can be very helpful to go back and reread the posts on your threads. It can take a while to wrap your head around these concepts.
A main one is the fact that when an alcoholic is asked to change their behavior---especially, the behavior that comes from their drinking----they will exit the relationship---choosing the alcohol over the person that they are dating, The alcoholic will let nothing come between them and their alcohol......and they will resent anyone who tries.
Yes, many will try to "act normal and nice" during the early part of a relationship---but, they aren't able to do that forever, and then the facade begins to crumble.
I know that this hits you hard. You bonded with him, and felt that you had found the person that you wanted to attach your wagon to his star. Being unschooled in the true nature of the condition of alcoholism,-----you are really shocked and bitterly disappointed as to how much he kept under the surface.
And, yes, I do think that his behaviors---like throwing the clothes at your head while you stood there crying is Abusive. It shows what direction he will take when his inhibitions are lowered (by alcohol) and he becomes frustrated.
By the way, this kind of behavior tends to grow worse, over time, as alcoholism grows worse over time. Alcoholism and abuse both tend to grow worse over time.
Hen....just so that you know....."Nice" guys are not just nice some of the time, or even most of the time---truly nice guys are nice ALL of the time!
There are millions and millions of men who never, ever throw things at their girlfriend or wife---or ever shove or pusthem....or, ghost them, etc.
We can see that you are heartbroken and are desperately wishing for a way to hold on to this relationship. It is common for the heartbroken to feel this way--and, it earns our compassion. You will need time to grieve this loss and to learn as much as you can from this bitter experience. It has happened to lots of us!
I fervently hope that you will read the book that trailmix suggested----"Co-dependent No More"
and---since you have implied that you have had abusive partners, in the past--I also suggest that you read the book "Why Does He Do That". I think it will really be worth your investment of your time....