We can't diagnose you. But there are possible medical reasons for your disconnect.

You need to talk with a psychologist. You could possibly be 'on spectrum' of Autism.

You keep referring to be neglected as a child. It might just be you haven't learned the skills and don't know how to connect.

You didn't respond to my question about if you ever had friends, people you enjoy being with. It sounds like you must be in your 20's. If this has gone on all your life, I'd think about it more seriously.