SuperDan, can I ask a question, and please don't take offense to it? How well do you know this friend? Like, you say you are far about, is this totally an online relationship, or do you know each other in person but moved or whatever? Because I have friends I've made online, some I've kept, others have left, and its always a good thing to worry about someone. But if its only an online thing, no matter how strong, and there's nothing you can do physically, you should also take a step back.
I don't mean distance yourself completely or ditch this friend in her time of need, but from the sounds of things, its putting a lot of stress on you mentally as well. You sound like you're doing all you can, but you also need to make sure you are handling yourself ok. Its never a good thing to stress yourself, especially if its something you truly can't do anything to help.
Just my two cents.