having a hard time :(

I have 2 beautiful children with my husband and I really want another but he doesn't. It's all I  think about. I'm finding it hard to be happy for anyone with a BFP, even family and friends. I'm resentful. I've tried convincing myself I don't but I do so badly that I'm resenting him and it's starting to really hurt our marriage. Has anyone gone through this? Any advice on how to turn It off? Will I ever get over it? I feel like there's this incomplete piece of me and I don't think that will ever change. By the way, I have talked with him numerous times about my feelings and I get nowhere.