Depressed fiancé (miscarriage)

So me and my fiancé had conceived and I had 2 positive tests and 1 negative, he is so tore up about me losing the baby as am I. I just don't even know what to tell him to make him feel better. I just want him happy and he's been depressed since we found out. I just need advice as to what I should say he has been crying for days and can't sleep at all and just mopes around the house...I feel like it's my fault that I lost it. I done everything I was supposed to and i still lost our little angel..💔💔💔