Below is my answer to the challenge based on the accompanying photo by C.E. Ayer.
Stone by stone he built his wall.
Around his heart.
Leaving a mistrusting, too-small doorway with a lock on it for second chances.
No one knocked for none had dared to trespass beyond the chain guard and padlocks.
Love crouched at the wall’s base, waiting, but was unable to grow forward, toward the gateway to his heart. Past the chain links of criticism, contempt, defensiveness, and stonewalling.