When did my heart become proof of love's way? I merely found myself lost within her.

This profound couplet captures the beautiful mystery of true love. The poet asks: When did my heart transform into tangible proof of this secret love? The answer, however, is that the heart never *became* the evidence; the lover was constantly, intrinsically searching for that secret all along. It suggests that love isn't a destination you arrive at, but a journey you are perpetually on.