I'm falling for my best friend?

Don't do it. Don't ruin the friendship. Part of the lure here is also the warning sign. A lot of women cannot get enough of the guy who treats almost everyone else badly except for us. It is the most powerful aphrodisiac. But, 2 things to keep in mind.

1. Someone who routinely treats quite a few other people poorly has a high chance of doing the same to you one day. And that chance gets so much higher if you try to change the type of connection you have. He could simply not see you as more than a friend and then not want to hang with you once he finds out you have these kind of feelings for him. Or, he could have a go at something and then when it doesn't quite work out, treat you badly.

2. Once you step past being friends, you can never go back. Even just telling him how you feel is enough to permanently ruin your friendship.

If you value the friendship, keep things the way they are.

I was in the same position a couple months ago, and now me and my bestfriend are dating and its great. so maybe one day when its just you and him tell him how you feel.