Most Helpful Guy
You have to take what you learned. You might need to have a handful of failures because you need practice. Learn what to say, what to do, where to focus your eyes, how you gesture, etc. I'm as shy as can be, my voice shakes and everything I do shakes around certain people. Jokes I have cued up in my head, practiced and ready to go fall apart, but as I keep meeting people and keep practicing it all falls together. So that's my advice about handling shyness and awkwardness.
As for missing the guy, well just think of the guy as a lesson learned. He didn't think you were worth his time, why is he able to rent a room in your mind? He's out, there's another nice guy out there who has even better attributes so take what you learned and get on with your life.
Most Helpful Girl
Most people on dating sites keep their options open. The rapport you had with him , will be the same for other girls who chat to him. He wouldn't have been talking to you exclusively, and he will probably be meeting up with other girls too. He'll ghost those he no longer wants to meet up with. You have to be prepared for rejection when you meet guys on dating sites.