You're not an idiot, you were just afraid. Happens to the best of us. I say come clean, admit how you feel towards her. Sitting around "guessing", asking friends, trying to make sense of another person's actions, is only going to drive you deeper into an emotional funk. What is the worst that could happen? You find out she doesn't like you the same way? The truth is scary, but confront it so you can move on with your life if need be.
You are probably making more of it than is there. If you wanted a relationship with her should have let on right away that you were interested like that. At this point probably thinks of you as a friend. There are plenty of women in the world but just relax next time and make it clear you are interested.
Hi and welcome. She obviously thinks of you only as a friend to text with and she does like you as she likes the other guy. I dont think you missed out any opportunity with her and i dont think she was reading your intentions about friendship as boyfriend girlfriend type.