wear down

verb2

1. •
   To cause (someone) physical or mental fatigue.

   • The eight hour shift in the mine began to wear Tim down after a few months.
   • (sports) To make the opponent tired after using a strategy while conserving own energy to attack later.
2. •
   To eventually persuade or defeat (someone) through persistent effort.

   • At first she refused to buy the kids sweets, but eventually they wore her down.