I completely have stopped caring on what the world thinks of me, is this a good thing?

Well I've changed my whole attitude towards life, I pretty much am aware of so much more that goes on around me then a couple of years ago but I don't get offended at silly things and argue like I used too, because deep down I don't care what anyone thinks anymore. I decided to study, for me not because thats how society expects you to be.( I dropped out of school at 14 and always cryed and tryed to study to impress family and etc but was not interested.) Then argue with the world and say "You don't know me I can do it" and then they would laugh because I would say it, but not do it. I travelled and then I decided I wanted something for myself and my future it was for me. My family ignored me cause of how I am. After years my mum calls me up and said she saw me on facebook and how much I have changed and wants to have dinner with me and my brother. All the girls I study with are my age (21) but they still talk like they are 16, gossiping talking behind other girl's backs, it's almost like they are copying the Reality TV. But I don't care cos I am so over trying to fit in and talking about complete nonsence. They start to look at me like I'm an outsider, but that doesn't let me down anymore! I don't have to try convince them that I can also talk trash and be rude and argumentive...Wheres that going to get me? I used to act just like this, but I was 15.