I'm glad you found out before giving her the birthday ring. To be honest, she doesn't sound like such a great friend either. If you have made albeit softer romantic gestures that she didn't take seriously because she wasn't interested, I don't think she should have accepted your gifts, especially jewelry. That statement she made at lunch just irks me...your giving jewelry and a valentines day card was clearly aimed at wanting to take the relationship to the next level. Her accepting the bracelet and then telling you she's going to wear it out with another guy for valentines is just throwing it back in your face. Sounds like she just wants the attention and doesn't mind the free gifts.
I say lesson learned, and stop the gravy train. You sound like a really sweet guy that deserves a girl way more considerate and worthy of you than she is.
Blessing in disguise I say!
Agreed!!!