I suggest one potential interpretation of your recurring dream. If you need to understand how the dream is approached here you could look at my earlier post about the core approach to dreams:
https://www.spiritualforums.com/vb/showthread.php?t=148158.
We may in this interpretation set aside and ignore 2 parts of the dream:
a.
my family forgot to tell me she was still alive and didn't actually pass away.
This is a false confused past.
b.
She's in my room or the room that she used to stay in which is right below my room sleeping resting. I go in and she's there and I just cry and it's as though I'm relieved of all the regrets I've have regarding her passing away and not calling or spending enough time with her.
This is a false future projected by the ego with a false resolution.
Only one part of the dream is of the Now and the Present. It is valid for identifying your present problem/conflict:
I have reoccuring dreams of my grandma still being alive.
The conflict expressed is that she has in fact passed away - but only physically! The dream world recognises for you that she is very much alive and available to you in the spiritual world - and very probably anxious that you recognise her continuing and ongoing presence, and experience.
Should this interpretation resonate with you, and only if it does, then:
You are to simply acknowledge - and even celebrate - your grandmother’s presence in and from the spiritual world.
This will bring truth to the situation, truth to yourself, and to your grandma. The recurring dream will stop recurring - and life for you and your grandma can flow forward.
The physical world is but a projection of the ego - as a basis and tension for us to learn about spiritual reality. The only Real world is the conscious Spiritual Reality inside each of us.