I think you are right in saying it is the hardest thing you have ever gone through, it Really was for me! still is at times.
As long as you are lovingly distant (and it sounds like you are) then don't worry about not leaving notes and being mysterious as long as you limit it a bit so that she doesn't think you are moveing on, but that you can live without her. Even if she does move out do not give up as she still seems to be interested in you.( it's not over until the fat lady sings) ; And just because she moves out doesn't mean it's done.
One thing i learned when i did that was that my H became more interested in what was going on with me. That showed me that he really was still interested in a R. It sounds to me like you GF is to .
You are being her friend and that is great you are listening and responding but not demanding and im'e sure she sees this. Baby steps remember.
Try keeping a journal of what baby steps have happened and also what has not worked and look back to check progress.
Try not to read anything into what she says and does as it makes things harder on you just take it as something nice at the time(easier said than done!).
I wish you the best of luck on the date to the wedding!
You are right it is such a fine line and i think when everything is said and done we are much better people than ever before in the end, and will be wonderful partners for whoever may be in or enter our lives from here on out.
You are doing a great job in my book.
JAK
You don't get to choose how you're going to die. Or when, you can only decide how you're going to live now. ~Joan Baez