Why Do Bieber Fans Get So Offended When People Say They Don't Like Justin Bieber?

Seriously, I don't like Justin Bieber and whenever I say I hate him, my friends get so mad at me. This girl is a HUGE Bieber fan and she used to be my friend until she found out I don't like Justin Bieber... It is so annoying! When I say I love the Jonas Brothers, everyone says "THEY STINK!" and whatever... Why can't people just respect other's opinions? If your just going to yell at me for not being a belieber, then don't both answering. Kk, thanks.