Just a gut 'momma' feeling but as I look back on the different stages of our son's baseball development, I remember times when he obviously pondered life without baseball. For him, the feelings seemed to last only as long as his feeling of 'failure' did or as long as his 'time off from throwing' for the season did, and by October/November, he was biting at the bit to get back on the mound. He is getting ready to head out to his 3rd full season of pro ball, and with all the trials and tribulations with that life, he still misses the game by mid-November.
From this woman's perspective, I look at it much as I would a romantic relationship that ends: if the necessary passion remains and the couple are 'meant' to be together, it will happen. Likewise, in baseball, I believe that if there is still a passion after a hiatus from the game, the 'couple' will get back together and it will be for the betterment of both. (And obviously, in some players' cases as mentioned by TPM, it can be several years with success still at the end of the road.) If that doesn't happen, we can only hope that the young people involved will find their true and driving passion elsewhere, for the betterment of both.