Thanks for the responses. You all have pretty much confirmed what I suspected was the right course of action. I still feel terrible, though. This girl has never asked me for anything ever. Always giving, giving, giving; to a fault even.
Can I even continue the friendship? I do not contact her, but I do respond when she contacts me. I have talked her through some tough times and have actually made progress in the way she deals with tough issues. On the other hand, I could be just as easily setting her back by still being reachable. She has a strong fear of abandonment.