The bitterness and the ache in your heart is something you definite carry around you. You may blame it on others. Yes, that others make you feel bitter and resentful and hurt is true... that they heap calumnies upon you and strike mercilessly at your personality is something that you will always expect. But the way that this will affect you will depend greatly on how you let it touch your mind.
Hurting people can affect society a lot. I mean they can affect people around them.
Positively, they can accept the hurts as part of the honing of their humanity... as something we can't live without given our differences and utter weaknesses. In this way, they become realistic, more comprehensive and patient towards the vulnerable fragility of others. In this way, they become conscious of the thing that may hurt others which may be what is causing them great pain.
Or, they may become hard-hearted, ruthless and bitter persons. When you carry the gloom of your hurts around you, you become intolerant, you become a frustrated and frustrating human being, scattering the bitter, nauseating perfume of bitterness around you.
The bitterness we feel do not often come from others. We often always carry it around, bringing it from our past.