青梅竹马网上的翻译有很多种：
childhood sweetheart
green plums and a bamboo horse
puppy love
不过个人呢认为第一个翻译的最为恰当,第二个有点生硬,第三个偏离了本意.
所以应该可以这样翻：
Though childhood sweetheart is romantic,but it doesn't belong to me,which I should have realized from the right beginning so that I wouldn't await you for so many years.