I'm glad you posted. You're not alone. I'm 5 years younger. I'm one of the most passionate people I know. It's difficult to take a leap, I rather be pushed :) .But I'm learning that the sooner I do make the change the sooner I can start living my life. +1 on telling your wife. Even if you decide to make a change tomorrow, it could be that it will take you 6 months to accomplish that goal. So I think it doesn't need to be something that happens tomorrow, but something you can work towards.
BTW great feedback HN peeps