I don't get it sometimes. Can't get pregnant.

My husband and I are going into our 8th month of trying and nothing. I realize this isn't that long at all and many people have tried for years. So I feel for you. Sometimes I just don't understand though. We're both fairly healthy people. Young. No pre existing health conditions that would affect fertility. I'm so frustrated with the whole thing. I stop trying and worrying, not pregnant. We try and track. Not pregnant. I'm not sure what to do anymore.