I work in an oncology out-patient office. I see all kinds of CA patients every day.
You can do some plans now:
1, memorable trip when you are stable, as long as you can take it. Take lots of pic and video. One of our PA’s hu*****and had stage 4 brain cancer. They went to Disney together with kids when he was stable.
2, family plan, do you want your parents come and visit?
Same family had a huge Thanksgiving party with both sides parents and siblings.
3, write letters to your son at different times when he turn 10, 15 and 20, etc.
Get birthday cards ready for him now.
4, get your will finalized
5, be positive, relaxing, it may be easier for you since you believe God. You can take his lead.
You are a strong lady, I really admire you!
Best wishes!!!