THIS IS REALLY BOTHERING ME, FOR YEARS :/ TELL ME SOMETHING I DONT KNOW?

Honey, we've all been in that boat. Hell, that's me right now. I don't really take the initiative to make friends so I'm stuck in the same thing. Whoever you're closest with, just ask them why they don't ever want to make plans with you. You seem like a person that needs that close bond, but haven't found someone that you can make it with. Just look for individual people, don't try and become friends with groups, that usually won't end well. Good luck, hope you make friends for the both of us. haha.