Stop thinking about how to impress her and make her happy, and start thinking about surprising and impressing the women who have shown you they have the qualities that you're looking for. You've done VERY VERY well to salvage a friendship that most people would have thrown deuces to. You've done VERY VERY well to dodge an arrow that was headed at your heart with the purpose to poison it. However, now that you've seen enough evidence to know that you're dealing with someone who you would not have a healthy romantic relationship with, don't let the genuine care you have for her drive you to acting stupidly. Sure, you don't subscribe to the "plenty of fish in the sea" line of thinking about people and relationships, but that doesn't give you a free pass to being a fool. You know what this is. Act like it.