Why do I feel like im missing a whole other part of my life?

Okay so Im 21 and in college.I just started at a new University and Im really excited, but I know there is something missing. All of my friends are getting married and having babies. Im attending 3 weddings this fall and winter and 2 baby showers (all for me friends) and all their husbands are Military(The expression "always the bridesmaid and never the bride" fits my life to a T.).Im born and raised military brat and Ive been patently waiting for my Mr.Right to come along.Im so afraid of settling for someone, but its not fair! I know I know life isn't fair, but what makes them any different than me? That's all ive ever wanted really.Ive always wanted to be a mom and have a good wholesome family. My friends keep telling me that it will happen sooner than I think, but they've been with these guys for years now and have had that constant companionship that I haven't. Ive dated,a lot actually. Im a good person who has a lot to offer someone and i've even (as bad as it sounds) been set up on blind dates. Im just afraid that im never going to get my perfect guy. Im so jealous of my friends and their happiness ( i would never admit it or let it interfere with our friendship) but I cant help it. Its like when ever we all get together to talk about wedding plans and baby showers ideas im always the one who is left out because i don't have experience in either of those. SO here is where i need some advice.What can i do to stop feeling like my youth and life is slipping away from me and not go crazy waiting for that special someone to come along and make me happy?!