I'm 29 and my best friend is 84. Getting relationship advice from someone who has been married for decades is invaluable.

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I had always been close with both of my grandmothers, maternal and paternal. However, during my sophomore year of college, my paternal grandmother stopped knowing who I was. Alzheimer's had taken hold, and though she's still alive, I've had to grieve what our relationship used to be. Not too much time later, just after I graduated from college, my maternal grandmother died suddenly, leaving me reeling from a different kind of grief, one that arrived without warning.