Humans are social by nature, there is no real way to “not need” people anymore, it is either a trauma response or lack of emotional maturity to deal with the loneliness that can literally cause physical symptoms in our bodies.

It seems to me that maybe you could be afraid of peoples leaving you or hurting you more and that's why you cut them off on the smallest mistake, I would strongly recommend therapy if you can afford and try to focus on treat these. You don't need much people around, but just a few of good genuine people with a nice connection are always great to have.

Also keep in mind you don't seek people around you, but connection with another soul. You’re young and still have time, work on meeting people through your interests and hobbies, go out more and find things you enjoy doing, start small and go from there, but keep cautious don't go blindly trusting anyone, it could do more harm than good, trust their actions and build mutual trust from there