Most Helpful Girl
If you don't feel like you can be the best for her, don't do it. Not only is it not worth it to you, it'll be worse for her because she'd be investing her full feelings. If it's not already, I think you need to make it clear to this girl that you're not interested in her that way. This way she'll be able to move on with her life and find someone else. Honesty, although hard, can be the best policy.
Most Helpful Guy
better try staying friends,... till u change yer mind? :-)