Two housemates, one mug left in the sink for three days. One of them washes it and says nothing. That isn't harmony yet. That's postponement.
Harmony with others usually costs a conversation. Harmony with yourself costs admitting which part of the irritation is actually yours to carry.
Living in tune with people has never meant agreeing with them. An orchestra is full of instruments playing different notes on purpose. What holds it together is that each one is listening to something outside itself.