Furthermore, when you're young you don't know shit yet, you haven't lived enough, you haven't made enough mistakes, you haven't suffered enough, whether by your own choices or the choices of someone you loved. In other words, CONFLICT AND SUFFERING ARE ULTIMATELY THE TRIGGERS FOR YOUR CHANCES AT SELF-BETTERMENT, and in the end are what you earn to be able to better navigate yourself.
Some of us take less time to learn this reality of existential life, some take a bit longer. But, THE CHANCE TO LEARN WILL ALWAYS BE THERE. ALWAYS.
Therefore, the older and more experienced you get, the better you're supposed to be at editing your life, and that includes kicking out people who are a stupid waste of your time and your emotional and social investment. You get to do that because you've been through so much already and you know better and that is your reason to tell them why you are kicking them out of your life. You get to tell them, as that is your experience, your assertive power, your privilege to exercise, and that is THEIR CHANCE to realize something about themselves that they must change.
You are giving THEM a chance to better THEMSELVES.