Reasons
 

Editted fo reason

Sorry to hear that :(
Just keep on respecting her and with time it will all smoothen out.

Wow, kudos for being a good friend and letting her know.

Umm, I dont know what to suggest, because if you both agreed not to be together on mutal terms, she has to show her friendship to you now, the ball is in her court.

Dont let her treat you like a standy by partner. As she got upset, its clear she has feelings for you, maybe talk to her to and ask her to tell you her real fealings with no bs.

Good luck

Thanks for the advice. I know time will sort stuff out, it's just the fact I feel so helpless to try and better it, because I am the cause. I'd be the guy she'd go to to talk about this sort of thing, but I've alienated myself by being truthful.

I know she has feelings for me, but I didn't realise they'd cause this...

Is it possible she thinks that your friendship is going to be jeapordized because of a new relationship?

I am one of those people that doesnt dump my friends of another sex (which most of my friends are guys) just because a new person "might" be uncomfortable with it. I do not believe in destroying a perfectly good relationship with a friend over a man who is too insecure to handle that I have other men in my life in a purely platonic way.

Maybe your friend thinks she's going to lose your friendship over this

You are not the cause. She is, by not being honest with you. Its her own fault. What should she expect, when you have mutually stated that you have no romantice feelings for eachother?

She went along with the "just friends" thing, even though she felt more. How is that your fault?

I have been through this... Very recently.

Go for the new girl. Your friend is a friend, if she has feelings for you she needs to tell you. Not hide them and expect you to wait around for her to decide that she will let you try and be with her. Go for the new girl, go with someone who is into you, not someone who wants you as a friend and nothing more, but also doesn't want you to be with anyone else. Don't limit your possible happiness on someone who doesn't want to be with you. If she wants to be with you she needs to make that clear. In the long run you will be better off...