If you found out you only had six months left to live, what would you do with the rest of your life? Do you have a "bucket list"?
I would make sure that my kids and husband are as prepared for it as they can be. I would write letters for them to read every birthday so they know their mom loved them. I would get my affairs in order so they aren't financially fucked from the funeral. Then I would try to do as much fun stuff as I could with them before I go.
I would probably go to a lot of concerts with my husband. And take the kids to an amusement park like Six Flags, maybe even the Epcott center and Disney World.