At a Loss

I have struggled with mine and my brother's relationship since..... well practically since birth. We aren't those siblings who grow up getting along and being all buddy buddy. We were quite the opposite. ALWAYS fighting. ALWAYS disagreeing. There's only a few occasions where I remember being ok with him. Now that I'm older and I realize how important family is, I try to be a better big sister. I'm very protective of him and I care about him more than he could ever know. I'm so incredibly worried about him, unlike me, he is very much a follower. In high school I was somewhat of a follower, but since I'm very outspoken and question EVERYTHING I fended for myself when needed and NEVER conformed to what people thought I should be. If mom thought I should dress preppy, I dressed in all black with chains hanging off my pants and blue gel in my hair. That's just who I was. My brother.... he is quite the opposite. He's outspoken alright, but instead of debating on what he TRULY believes, he debates on what everyone else thinks he should believe. It breaks my heart knowing all the things he could be doing, and knowing that underneath the surface is this incredibly kind and loving guy who just wants to be loved and fit in. Why are teenagers so cruel? Why can't they be more accepting?