The phrase "wore down" implies a gradual loss of strength or energy, and there are several synonyms that can be used in its place. "Eroded" suggests a slow but steady wearing away, while "fatigued" implies a depletion of energy or stamina. "Diminished" or "weakened" also convey a sense of decline in strength or effectiveness. Similarly, "erased" or "obliterated" can be used to describe a gradual disappearance or reduction. "Exhausted" and "spent" both denote complete depletion of energy, while "ground down" and "whittled away" suggest a gradual wearing away over time. Regardless of which synonym you choose, each emphasizes the idea of a slow and steady decline.