Loosing it!!!

Brittani
Hey all! This is my first time posting. Guess  I'm at my whits end!!! DH and I have been TTC for 2 years this month. I've been prego once and my daughter(4) was born at 26 weeks...he has 4, which include a set of twins. I've seen a doctor and all tests came back normal...IUI once and it didn't work. I don't know what else to do...