What does it mean to raise a white flag in love?

Holding a white flag in love means surrendering and giving up. If you put it in the emotional world, you have paid so much for love. There is a strong side and a weak side to make each other strong. Often in the end, the one who really loves more is the one who is injured and silently quits, holding a white flag, because there is really no way to love anymore, and chooses to surrender, give up and quit.