What I believe, according to my own experience, is that a calm, peaceful mind is a very important element for sustaining the body in a balanced way.
Through violence, you may 'solve' one problem, but you sow the seeds for another.
Religious belief is not a precondition either of ethical conduct or of happiness.
Genuine happiness and compassion go hand in hand.
World peace must develop from inner peace.
Distrust brings frustration and fear. So therefore, the lonely feeling automatically come. So, lonely feeling is not creation of environment, but creation of your own mental attitude.