One thing I have learned in life is that very few people have found out how to be at peace with themselves. Because they have not found out how to be at peace with themselves, they turn to many methods to fill them selves.
Lets just say these people have a giant hole inside of them. The only thing that can fill that hole is being at peace with themselves. Well there is a HUGE hole that needs to be filled, so these people turn to sex (cheating), drugs, dwelling in the past, leaching off of others, gambling, getting drunk, over eating, under eating, etc to temporary fill their empty void. Some people even commit suicide because they can no longer take their starving sensation of finding peace.
The worst part about this all is many people don't realize finding peace is the solution. Some people may know what to do, but are not willing to take the difficult steps to be at peace. Why are some of the richest people in the world so miserable? Why are some of the poorest people in the world so happy? I've seen people who have had difficult lives be very happy people because they are at peace.
Before one can teach others how to be at peace with themselves, one must be at peace with oneself. If the teacher hasn't had mastery of the subject at hand, how are they going to teach their subject to their students?
Some steps to finding this peace is first looking at oneself. Are you really right? Try to look at what you have and not look at what you don't have. If you have been wronged, try not to live in the past and don't harm others (I know this is easier said than done). Focus on your strengths and not your weaknesses (But still accept your weaknesses).
Once one can accept oneself, then that person can learn to accept others as well. Not only that, but they can also teach others to be at peace as well. Now you may not be successful with many people in life (in terms of teaching them peace), but being able to accepted yourself will allow you to accept the fact you can't help everybody.
Anyways, that is how I try to live my life and it makes things MUCH easier on myself. Sometimes we can all slip and go fall back into our holes (Including myself as this thread is a testament to that), but all we must do is get back out and fill it up with peace again.
Don't give up hope because giving up means you will miss opportunities to find wonderful people. There are good people out there who have discovered peace. I know it is very hard to find, but when found it is a very beautiful thing to witness.