Am I just a horrible person?

Today my husband told me that once again a couple we know is pregnant. I immediately went into a deep depression and just had hold back the tears. It's been over two years i have tried everything. I have been diagnosed with unexplained infertility by multiple doctor's. I am so tired of being sad all the time. I wish I could say that seeing someone's pregnancy announcement makes me happy, but it doesn't. It just brings a deep sadness and self pity. My husband tells me I am selfish and he becomes frustrated if I cry about it. So I often cry myself to sleep. But how am I supposed to feel. My situation is hopeless at this point.