Anyways, I think that there doesn't always HAVE to be a reason to be friends with someone, just because it makes you happy to be with them is all that matters. Friends stay on the same page, understand what the others are going through and always accept each other no matter what things may seem like. Also believing a friend when they suddenly change personalities, attitudes, or look.
Stick with your friends and they'll stick with you. It's a lot of work, but like most things, it's worth it.