Not Interested....Not excited for the next cycle

My Fiancé and I are having our engagement party this Saturday. I am supposed to feel excited but I'm feeling defeated. I love this man with all my heart but after the miscarriage I have not been able to conceive. Doctors say I have no fertility issues and all tests are normal but I cant help feeling like I'm setting him up for failure. What if I can't produce a child? He says he loves me regardless but I guess that's easy to say when there's hope.....