realize I needed to spend more time with her
Both of my grandmother passed away when I was in my teens. I do wish I was smarter then too.
An yea I do dream. Some of them are completely crazy and make no sense at all or where that came from. Some are more like every day things - like your grandma dream.
I spent a lot of time with my Mother's mother (Ida) and knew her very well. It was that relationship that made me realize how much I had missed with some of the others. I know you can't always know these things are so important when you are young.
I on very rare occasion have a nightmare and those don't make any sense at all mostly. Fortunately it doesn't happen much.
The other dreams are not all based on real things, but somehow they still seem normal while I'm dreaming them. Interesting.... and odd.