At some point when I was so much out of shape I couldn't hit a ball. then I was back to the gym and playing in a couple months.
I think I can't lose interest when it comes to golf, since it is so much more to me than just playing and keeping my score: it's traveling and seeing the world around me, meeting other people and studying life, enjoying the nature, the history, the beautiful views and the pure aesthetics of great golf course architecture. It's also teaching others, studying biomechanichs, physics and so much more. You can't really get enough of this.