Harmony in world comes only when it is in us. If peace is in our soul,in our mind than we spread it to others with whom we interact. It depends upon our level of peace .If the other person is disturbed then his high level of negative feeling can overlap our positive feeling and make us unhappy too. 

      So to stop that our level of peace should always be higher. Take an example of saints, they are so peaceful that when we interact them we pleased . Our disturbed mind gets peace. Their level of peace is more than our negative feelings. So do you know how do they get such peace ?

     They get peace by doing meditation and positive attitude.Their aim in life is to get peace in mind. 

     If we turns the pages of history we find many people left their houses and went to forests in search of peace. Does it mean peace is in loneliness ?

No I dont think so,  

     "Peace comes in balanced mind "