L., this young man is not ready to commit. Perhaps because of money, but more likely because he's just not ready to marry. He may have been staying in the relationship with you because it was more convenient than finding his own place without you. If he were really, really committed to you, he would be moving heaven and earth to find a way you could stay together.
My suggestion is that you face the truth. He has moved on, and until you accept that, your heart will stay chained to a man who doesn't even exist. At least not as you picture him. Your ideal of him lives only in your head.
Take whatever time you need to grieve this loss. Women have been losing men they love for the whole history of humanity. And we survive it. And then, often, when we have made peace with it and gone on with our lives, somebody comes along who is even better for us. This has happened to almost every woman I've ever known. Including me.
You can go a year without him. You can go a whole lifetime without him. It's up to you to make your life better, starting with the reality of it, right now. You can do this.