Is it normal that i want to keep in contact with my favourite teacher?

Sometimes when I look at my favourite teacher I want to go up to her and say something but I don't. I practice what I am going to say to her but when I walk, slowly going up to her I forget how to put it in a sentence how to ask her a question if it's not related to school and she is doing something important. When I walk to her and am determined to tell her how I feel she ends up being on leave or away, sick. I am leaving soon and want to ask her how we can keep in contact but I am afraid that she doesn't think that we are that close. I think we are but I don't know if she does.