I don't think there is anything wrong with introversion. I have some introvert tendencies. What I find annoying in relationships is that introversion is used an excuse for poor communication. I think the issue here is most likely anxiety and conflict avoidance tendencies rather than introversion. If she can't figure that out and be a better communicator, to at least a person she wants to cultivate intimacy with, it's going to end badly.
Yeh take it slowly. And if she doesn't bite after a few messages, completely let go and move forward with your life. If she wants back in, let her come to you and do the work. Live your life and be happy for yourself.
