Yes, it can happen. I really understand - you're in transition, aware of how much better you and life can be, and unlike many people, you understand this comes from within! But you're not there yet and unsure how to fix it.
Sorry if this is a bit waffly but hopefully something of what I am about to write will be absolutely relevant.
You ask why your friends behaviour bothers you. One thing I learned which has stuck with me is to trust your feelings - if you feel hurt, or insulted, or devalued, this is a response from your brain, your morals, your inner protection of your emotional safety. Don't ignore it, but cherish it. Use it to guide you and make the decision that you will now take control and move on to better friendships and relationships. I think you may have slightly 'disassociated' in order to protect yourself from emotional hurt or rejection. Cutting people off is almost another way of doing this (deep down you know they're not a good influence, perhaps?). This may be something you learned to do as a child, if your parents didn't talk through things or validate feelings to let you trust yourself.
Mirroring the emotional relationships in childhood, we sort of attract the same people into our lives as adults if we don't address it. We are an easy target for emotional abuse, we accept it as "our lot" in life, or that it happens to us because of "how we are". That it must be something we're doing wrong. That we're worth how we let people treat us.
Be alone for a while, even without friends if need be, work on becoming strong and true to your morals or whatever 'truth' lies in your unique soul. If you are aware of negative thinking habits, change them. Do things that nourish your soul - interests, creative things, reading, even just the sort of tv you like! Be happy to be just the way you are. Accept it and know that's more valuable than moulding to others. Attract better people naturally, by being 'you' and not flinching away from accepting nothing but respect and love, and eventually you will grow bonds with better people. It may feel selfish at first but that's because you're used to doing what comes instinctively which is to just fall into friendships with shallow, easy breezy people who ultimately don't care about you.
You don't want to attract those who can take advantage of your emotionally (by manipulation) but instead people who validate you, lift you up and respect your feelings.
When this happens and the toxic people are removed and you allow yourself to grow only worthwhile bonds, you will get to the stage where it comes naturally to do this in return ("be a good person"), and your emotions with return, you will be able to laugh, cry, express yourself genuinely. It takes time but is worth making the changes. Take control. You are no longer the mould of your family at home growing up. Good luck!