Your problem is no longer that you doubt yourself or that you question your likeliness of finding someone else who's interested. You know better now. You know you have options.
But you're not interested in those other options.
Because you've already made up your mind that this will work out. Because he said it would. Because you're willing to do everything in your power to make sure it does. Because. Because. Because.
You know you can do better, but you're not interested in better, you're interested in him. You have the smallest suspicion that this relationship won't work out because the signs are all there: he's not really ready for a relationship, he's too occupied with making paper, with himself, with changing you into the woman that he really wants. Not to mention that he doesn't care that he hurts you, that he tries to buy you with money and endless empty promises. That you feel just as empty when you're with him as you are without him.
You gave him your heart.
You have all the faith in the world that if you stand by him, if you just wait it out, everything will be okay. It's just stress. Just a phase. This will pass. Your relationship will revert back to what it was before he started taking you for granted. Before you got too comfortable.
But the truth is that he's already made up his mind. He mistakes your kindness for weakness and he wants a strong woman by his side. You're just there to fill the void in the meantime.
Somewhere along the way he lost his faith in your relationship, or maybe he never had it to begin with. You need to recognize this. Then you need to walk away; he's not worthy of your time.