Re: Dealing with a Friend that Left Islam
You've done all you can. Don't bother anymore.
If she wants edification for her various questions, just tell her to log onto this forum.
I don't think telling the person to "read" the Quran will help much, as they'll just be biased and mentally destroy or subvert any context to the handful of versus that she has issue with.
It is nigh impossible to show one how to believe. That comes from the inside. Conformity is imposed from the outside (often, though, in a consistent manner with how the bulk of people believe). Perhaps she simply conformed, and never did believe in the first place.
There is more to religion than ritual. I don't think your friend ever grasped that. Now, being a part of a society that takes all achievements and associates it with their "way of life" (a tenuous connection at best), it's going to be hard to show her a "better" way in any concrete terms. You may just end up dragging yourself down into a depression in the end.
Sometimes you have to stand back and except the world, and the people in it, for what it is. Don't let it overwhealm you. Her loss of faith shouldn't be a loss of vindication in faith for you. I mean, that is what bothers us when we here of this kind of thing, no?