Will I be the only one left?

My little sister is pregnant. Two of my best friends are getting married within a year of dating the men they are marrying. I think I'm equal parts thrilled and sad at the same time. I'm thrilled for new life and for new marriages (especially marriages that I endorse whole-heartedly!). However, I'm sad becuase I feel that once again I am getting left behind. The friends and family that I used to have so much in common with are passing me by and I am plugging away in Miami...tolerating it, but no way at home with it. They are "settling down" and I am beginning to be known as their crazy friend/sister who doesn't have the same address two years in a row and has a different boyfriend every couple of years. It makes me feel alone.
I still don't know what I want to "do with my life." Do I go to grad school and get my MSW, do I teach, do I just stick with the not-for-profit world, do I work at at church? Here, there, everywhere...I don't have a permanent address or a home phone number, or a personal computer. I'm in debt becuase of living a year of service. I'm just not too thrilled with my situation right now. I'm not asking for anyone's sympathy or even understanding....I'm just venting. I'll probably erase this later.