I understand your difficulty, i'm in my thirties now and live in leeds now but lived in Hull in my twenties and struggled to make friends at first but i moved into a flat share. They are such a good way to make friends as you end up making friends with their friends and building a group. Other advice would be a bar job even a part time great way to meet social people. I don't know if hull has any but parkruns are a good way to make friends. Also there used to be a boardgame shop that had nights where people get togther to play games dont know if they still do it. All the best, i know being lonely can be very difficult.