You are at that horrible point where you are considered an adult, but are really just a messy mixed up solution made up of differing potentials of which some are just finally starting to crystallize into the person you will be.Or in other words be polite to everbody and do lots of things and maybe you will shake down into a person you respect and can understand. After that it should be easier to find friends you relate to more, Just remember people are not to be used abused and thrown away.
Well, maybe you haven't found the group in which you feel completely comfortable and yourself with yet. Remember the rule-------- make new friends but keep the old. I think it is fine to add to your friends but you don't have to alienate the group you already have. Don't ignore your current friends but expand your circle. good luck