Hello & welcome. I'm sorry you have to be here but I think you'll find a great deal of support. I can completely relate to what you said about feeling like you're letting dh down. The thing to remember is that DH married you completely, not just your uterus & ovaries. The IF road isn't easy or for the faint of heart, but ultimately I feel that it has strengthened my marriage. You guys are partners in this, just as you'll be partners in raising your family, regardless of how you create one. Perhaps counseling (either you alone or as a couple) would be beneficial to you.
I agree with PP. Are you seeing an RE or an OBGYN? I highly recommend seeing an RE if you aren't already. There is a lot of testing out there that is beyond that which many OBGYNs do. A SA is another great idea to make sure that DH is okay. I'm not sure how involved your clomid cycle is, but please do not take clomid without ultrasound monitoring and bloodwork. An HSG is another test you should have done prior to that to see if your tubes may be blocked. All the clomid in the world wont get an egg through blocked tubes.
I hope your stay with us is short and sweet, but in the meantime, take a deep breath & remember we are here for you.