Become bitter
Examples
Old friends become bitter enemies on a sudden for toys and small offenses.
We barely have enough time to figure out who we are and then we become bitter and isolated as we age.
In the struggle for human rights and justice, Negros will make a mistake if they become bitter and indulge in hate campaigns.
It's hard to recover. You become not so innocent. You become, in a way, more sophisticated, which I think you shouldn't. We should all have more simple happiness.... You become bitter.
Maybe people become bitter when they don't know what they are fighting for. But I keep my eyes open.
We must work passionately and unrelentingly for the goal of freedom, but we must be sure that our hands are clean in the struggle. We must never struggle with falsehood, hate, or malice. We must never become bitter.