Is there any way to save my friendship?

A couple of months ago I realized I had developed feelings for a really close friend of mine. I asked her out and she said she needed time to think about it. Throughout those 2 months my feelings for her grew even stronger. Just when I thought things would move forward, I found out she had a boyfriend. I became angry, I think I had reason to. She never told me she had one, instead she kind of kept me lingering around her for a long time. I don't really care about the feelings I had, I'm pretty much over it, but I hope to rekindle our friendship. Help =]