Hatred is like a slippery slope:
easy to descend but arduous to scale.
Most of us have undergone emotional upheaval as a once loving relationship mutated into an acrimonious one. I would imagine that far fewer of us have managed to transform hatred into appreciation and love.
The slide into hatred can begin with our teetering between excusing the other's behavior and justifying our feelings. Then we start to cast blame and look to absolve ourselves.
The other person acted unreasonably. We behaved admirably.
They are guilty of wrongdoing. We are innocent.
Our smoldering emotions erupt, and we fly into a rage. Hatred hardens in our heart, an uninvited guest who has taken up residence. We need to realize that whether its cause was unjust or valid, we were wrong to succumb to hatred, allowing it to fester and grow. Instead of ending our suffering, we increased it. Rather than helping all beings, we injured them.
Such is the terrible price of descending into hatred.