Is it normal to have a really close friend and ditch everyone else?

So, a couple years ago, I had no friends. I was in college, and couldn't find any friends on campus. Then, one of my "forgotten friends" called, and we became like best buds. Then, eventually I made new friends, but hung out with the one friend more. Then, I started canceling plans with other friends to go with my "best friend". Is this normal? :/