I honestly hardly knew her in the grand scheme of things. She was just so special it pisses me off how she died so young. DEATH is the enemy nobody conquers except delusionally by "belief."
Not to say that it wouldn't have been nice if you two would have kept in touch but I'm guessing that if you'd have known her for an extended period of time and had come to know her faults, you may not have such a rose colored image of her and maybe you wouldn't feel so much to blame.
I'm getting older than old. At Seventy, I'm in the killing fields and in the crosshairs.
Everything suddenly has "final value". It's a going-out-of-business sale on APPRECIATION.
It's natural to take stock once in awhile and adjust ourselves to the changes time brings. Hopefully you won't hang onto this "older than old" thought for too long. That way when you are 80 you'll be glad that when you were 70 you didn't miss out on anything or start limiting yourself, just because you began to think of yourself as old. I'm sure there are plenty of 80 year olds who would love to be only 70 years old again.
Remember, anyone who is alive, no matter how young or old they may be, is in the "crosshairs" and can wind up not alive at any moment. Make up your mind that you're going to do your seventies with the same style, grace and humor you've shown thus far in your life. Be and inspiration to those who are coming up behind you, (me included) show how em' how it's done.