I'm probably late to this but I found a site called Talk to Books where you can ask a question and it references thousands of books to give you an answer. I asked it "why am I so lonely?" and I got:
Maybe you realize you have plenty of people you have fun with, but nobody you can turn to when you need someone to confide in.
You might have arranged your life so that you do not have to talk with anyone, so it may be difficult to meet new people who could become friends or dating partners.
Ouch 😫