Here's my 2 cents....
I am 22 years old. A lot of my friends are married, and a few have children. There are several people I went to high school with that graduated and became mothers also. At first, I felt left out and like I was missing something. But now I have come to realize that I have a wonderful life with what I have! I graduated from college, I have a real career, and I have a wonderful boyfriend. Him and I have discussed the future together and we have determined that we are going to have fun now, and then start to focus on our lives together. We both want to do so much before marriage. My advice to you is to enjoy your time while in college. You never know, you might meet that special someone while you are there! That's what I did!
It'll all fall into place, you just have to give it time!