I'd go hunting. I would also talk with her about how important it is for you. Perhaps do something nice for her.

Besides this being something that you've been planning for a long time, you never know how much time you have left with your dad.
Had I known mine would be passed away when I was 31, he was 58, would have spent more time with him. And my father in law was in an accident last year, which left him paralyzed.

Basically, looking back, I regret not spending more time with my family, than I would about not spending one day with the wife/girlfriend.