Depression and TTC

Does anyone else feel really depressed while ttc? I keep thinking that it'll never happen for me. I'll never be completely happy without a child of my own. I cry just about every day. It's so hard when everyone around you has babies or is pregnant. It's also especially hard when people ask when you're having a baby. It takes everything I have to not break down. It's getting to the point where I don't want to do anything except lay in bed. Am I alone?