My late father had a brain tumour, Mollee, he did not have seizures, however. His was in the area of language.
Unsolicited advice: simply enjoy each day, hope for the best, and don't worry about tomorrow.
If you can change the things you hope for, you will be able to laugh. I looked for the diamonds each day, as someone suggested to me.
Your husband's sense of humour is important, and you'll find great joy i the laughter in this poignant time.
all the best,
Jennifer