I played hardcore amounts of tennis from age 13 until about 29, as well as coaching, running tournaments, and serving a short stint at the USTA. Around that time, my son was born and my "real" career was taking off, and I just decided that enough was enough with tennis. I wasn't getting as much out of it for all the effort I was putting in... and the fire was gone. I ended up focusing all my extra time into my job, family, and the occassional game of golf (I got my handicap down to 14).
However, about two years ago, I realized I was getting too fat and needed to start doing more exercise. I ended up watching some tennis matches on television and decided that maybe getting back into tennis was the right kind of activity for me. Much to my surprise, after a few weeks on the court again, I was fired up. I played in a couple tournaments and lost to players that I would have beaten in years past, and my competitive juices were stoked. Now, much to my wife's dismay, I've played 26 tournaments in the past 26 months and am really looking forward to achieving some goals in 2007.
Sometimes the desire fades and we need a break from the game, but that doesn't mean that you won't fall in love with it again.