It's all in your head. There is one acceptable reason as to why you can't express your feelings towards others, and that reason is because you're telling yourself, I can't talk to that person because I'm too shy. Then, you don't talk to them because you think you're too shy. It's a vicious circle, and it won't stop until you start. Shyness is in your head. How can you expect to progress when you keep telling yourself you're too shy or you're not socially adept and do nothing? If you overhear someone talking about something you know anything about, say something. It's not hard at all to find someone with common interests. Just go out there and meet people. You can't expect other people to meet you. You have to do it yourself.

Get out of your comfort zone. It's not that bad. Give it a shot, you'll surprise yourself.