Friends grow apart, it happens. Making friends gets more and more difficult.

You can decide how much effort you want to maintain relationships, and how much you invest in new ones.

It looks like you started a journey of self improvement this process can last a lifetime. At some point I discovered that people are really interesting and diverse, especially as they grow older

I think there is a celebrity book “How to talk to anyone” that would be helpful. TL;DR - interview people