Hi Jessica,
Welcome to TeenHelp
I wouldn't normally suggest this, but do you think it might help if you listened to some other songs instead? It is good that they have touched you in this way, but don't have them make you forget that your grandmother is still here and loves you very much.
It's tough when people start forgetting, but it happens sometimes. It's really sad, but just remember all the good memories you had with her and try and spend some more time with her before her time is up.
Stay strong and all the best to you and your grandmother.
Nat.