Thank you @denverpilot. Great advice. As much as I still want to scream at him for the way he acted, I'm just going to let it go. I don't want to lose that Delta captain inheritance lol.
Mass Pilot,
Back in 1971 I married the love of my life and soul mate against the wishes of her parents. They eschewed the wedding and didn't speak to us for three years afterward.
She's agreed not to get him involved in my go/no-go decision again and regrets doing it this time. Now I'm not sure if she'll go along with not telling her parents that we're going flying, but I'll try to get her to at least wait until just prior to engine start.
Imo, that's the best way to handle it. FIL seems to be the controlling type. The less he knows about your plans the better as long as you and your wife agree.