"Quitting"-- is too drastic of a step IMO... I've said it before on here, but I was a super bad kid in the '80's. I quit school, and left home at 17. The only thing that kept me from a long prison term (I've had some short ones though!) was the stack of dirt bike mags, and the hopes of racing someday. W/o getting into the boring details of it all-- I finally did accomplish my goal. I wasn't any good-- just a slightly better than mid pack "C" rider. The experience was everything I hoped it would be. That was then. I'm going to be 43 next week.
Now? I still love riding bikes more than anything else. It's something that I want to keep on doing. At this point, the whole deal has come full circle. I'm back to where I started before it all got complicated with racing. I started off on a simple trail bike play riding on trails and backyard tracks. Now... I'm back to just jacking around on pit/trail bikes for fun. Sure-- I may pick up a 125 here and there. But I'll mostly stick to Smith Rd. and maybe the 'Cabin.
The thing is-- there's more to the lifestyle than just racing bikes. Dirt bikes is a way for me to stay connected to my riding buds and it keeps me on the path that got me to today. I love to laugh with my friends about stories we've laughed about a thousand times, making fun of the other guys' riding styles-- stuff like that. The local "elder statesman" have our own Jody's Box type of gang.
As one of those "elder statesmen"-- It's my advice to keep on doing what you love, but tone down the parts of it that broke all your bones. Hope this helps. --L*64