Glad it wasn't a glioma!

I've been through similar (brain cyst from an infection rather than a tumor).

I learned a couple of lessons. The top one was to not stress about it or anything else but to focus everything on getting better. Learn (and use) the names of your nurses and orderlies. Post brain surgery, you might be water-restricted as that balance system might be disrupted (mine was). Do not just refuse all food because you're impossibly thirsty. In spite of Maslow's needs hierarchy (and not feeling hungry) you still need protein or you will lose muscle once the fat is gone.