I really poisoned myself with all the hate and anger I cultivated when I was a teenager and it took some years to get rid of these negative mental habits.
Hate and anger were part of my life, and they almost ruled with me in some period. Being trough war, hunger, insecurity, fighting every day for resources put lot of hate in me.
I must say that I have use hate in some situations to help me in coping with some stuff, hate can give you reason for living, it can give you strength to survive, but it is temporary, and later you pay for that.
Just like rage, and fear, it is much better if you control it, instead let it control you.
Sometimes they are still here.