The fact of the matter is this: Right now you're friends with people at your school because you have to go to school there and are forced to deal with your environment and those who are in it. In other words, you're thrown into this mix and have to make the best of it.
In college, at least you're able to make more of a narrow bandwidth of your enviornment, maybe you'll hang out with folks because you share a common interest/Major.
IRL, you get to make all the choices. You get to choose if you want to hang out with friends from work, or old college or High School buddies, etc... Essentially, you get to choose who you want to hang out with and because of that you'll make "Life-Long" friends.
Don't get me wrong, I'm not saying your present friendships aren't important to you right now because thay are, it's just that friendships as an adult are different and what matters to you now in your friendships are not necessarily the same later in life.
"Woodsy" (a life-long friend) and I met in high school. We were marching band/Drum Corps fanatics. After high school we marched in drum corps and kept in-touch with other because we used to see each other on tour (He marched with the 27th Lancers from Revere, MA and I marched with the Blue Devils from Concord, CA). And after that, we taught competitive high school marching bands in the same circuit and saw each other every saturday night during the fall during marching band season.
But I gotta tell you, if it wasn't for that 'common interest' we would have surely drifted apart.
The reunions are a nice thing to attend. My tenth year reunion was F-U-N and my wife couldn't believe the kind of folks I hung out with becuase I'm so different now.
Ask yourself this; are your 'life-long' interests really the same as some of your friends? Be true to thine self first!
Congrats to all of you 2003 grads! There will never another senior class like you.