At first you'll be the best of buddies, but over time, as your friendship grows, you'll both start to realize that there's a fundamental conflict in what each of you wants from the friendship. Your individual but equally important needs probably won't ever be in sync. Your friend will end up taking on the role of the more independent person, the one who needs a lot of freedom and alone time.
You'll take on the role as the needy one who wants more of your pal's attention. These characterizations might not be totally fair, but they'll take on weight and dimension through the course of the friendship. You'll start to realize that you don't feel supported or appreciated by your pal, and this will be irritating, to say the least. If you both decide you want to maintain the friendship, your buddy may actually be the one who needs to make the most adjustment.