Listening to the soundtrack is definitely the best way to get on the mood. Watching some of the scenes on Youtube is also fun when you don't have the time to play the game yourself.
Maybe taking a break from the game would also help. If you let it collect dust for a while, playing it again might feel like a fresh experience. I haven't played GF in such a long time that I've actually forgotten most of the puzzles in the last two years of the game. I bet there will also be lots of dialogue that I've either missed or forgotten. When I have the time to play the game properly again, I'm sure it will be a great experience.