What was a better way to handle this?

Don't sweat it dude, you meant no harm at all and are completely right in rejecting her if you were just going to be attracted to other people. If I were you I would've told the best friend that It's between me and her and It's not going to change. After, I would go find the girl that likes me and I'd tell her that she's an irreplaceable friend, but I don't think of her that way. If she were to still storm off and delete me from facebook, her contacts list, etc. then so be it. I'd feel content with a clean conscience because I did all that I could in trying to save the friendship. Sooner or later, that girl will realize she made a big mistake with her temper tantrum and surely regret what she did. It's not good to force yourself or to force others into a relationship. The reason it is called a relationship is because the emotion of love is mutual and in relation between the two people. I hope you can clear things up and find out the right way. :)