Depression

I try to convince myself I'm okay with being the crazy aunt. I successfully convince myself until someone close to me gets pregnant. So my husband and I moved in with his single friend. Well about 6 months into living with him he moves a girl in without even asking us. Well it's been a year now since she has moved in and taken over the house. It is way past our time to move out and get our own place. Well they told us the other night they are pregnant. I'm sad, depressed, and angry. My husband and I have been ttc for 12 years now, this news of theirs just broke me. It's only been 3 days since they told us and I cant take it. They are already getting on my nerves, the baby this baby that. I'm over it. I know life isnt fair but damn. Everyone I know has had a child. Will it ever happen to us?