I think you need to find yourself again first. Surely you are not going to let somebody else decide for you how you are supposed to feel?

And on second thought, the speed at which he decided he wanted to marry you does put up something of a red flag. Its possible of course, but it does not happen often.

But what he is doing should not bother you any more.
You have your own life to focus on. And you will most definitely find someone who DOES deserve what you can give them.