Interesting.
From what I've gathered, you're quite compassionate about this girl of yours, but my main focus here is the need to find out why you're so silent.
I fully understand that shyness exists and is perfectly okay, but to always be silent? Not the best move. Is this something that is bottling your emotions and not allowing you to express the true you? If look deep inside yourself and find that being silent is who you are, you need to roll with that, and you will be accepted for you. But what you should not do, is be rude about it. What I mean by that is, when someone asks you a question, simply answer it, it doesn't have to be an essay, just give your opinion and end it, you don't have to be the life of the party, but just talking a little is needed.
Also try to be in a good mood. I'm sensing that something is bringing you down and not making you want to be happy. You also need to smile, I know it sounds stupid, but just smiling for the sake of smiling makes you feel a lot better about everything.
I hope this helped you in some way.
*Edit* I'll rephrase this bringing you down part. I'm meaning something other than this issue