Don't date someone you don't care for anymore, regardless of who you plan to date next. Break up with him now. Life is too short to affix yourself to people you don't care for or people who don't genuinely care for you. In addition, you're actually doing him a disservice by staying with him under false pretenses. Forget what others say. Live life for yourself. Honor yourself first while also being respectful to the feelings of others (i.e., don't cheat on your boyfriend). It's best to wait a bit before chatting up his best friend. Remember, too, that it's not all about looks but about respect and emotional connection. Slowly develop that with this other guy and see if there is a real chemistry there to build a relationship.