How to help her fall in love with me?

[JJWJ]

from a former mathematics teacher (male) who did not consider marriage before age twenty-four ...

First, Mark, before addressing your question, I want to make sure that you understand what your primary goal should be for the next five to ten years -- namely, develop yourself to become an adult living in today's society.
-- Spend time in becoming educated and in educating yourself.
-- Determine your goal in life regarding future employment
-- Continue to learn more of who you are

As to your question:
1) Admire that girl for staying off of facebook and avoiding a catastrophe which often happens to those on facebook.
2) Admire that girl for not hanging out with any boys.
3) A person who is shy (introvert) has many talents that one who is extrovert lacks. And vice versa. I had absolutely no problem with being introvert at your age and throughout life.
4) Are some people going to judge you, Mark, at times? Yes, some people are like that. Everyone is judged at times. You need to drop that fear and just be who you are.
5) Winning over girls is very improper and often leads to a hazardous adult life. ("But, I thought it would be wonderful. Now I have really lost.") Note: Steer clear of girls who want to be won over. They hope a man will rescue them.

When the time comes for you to find a young lady to become your future bride, you will feel it.