I have always been looked down upon, treated as a misfit, sneered upon and insulted straight. i always think about why I still continue to treat those very same people with the same  affection and kindness. 

I think it must be because of my upbringing and the values that my parents taught me through their life as example. They also were mistreated a lot of times by their relatives and sometimes acquaintances. However, they used to never argue or fight but kept behaving cordially towards all and it takes a lot of willpower to do it. 

My brothers and I grew up watching this and continue it even though some people are still trying to insult us. 

I did notice along the way that, if we behave normally towards those that insult us, they are actually beaten and their egos deflated thus leading to their mental transformation and change of attitude. If in the other hand, we react or respond to insults, then the arguments can turn into verbal conflicts thus causing huge rifts in relationships. It is better not to get into an unhealthy argument. 

There are exceptions and some will never learn.

As an answer to your question, I would still do good and am doing it right now to some relatives who think bad of me. What they think speak or act is their problem and their karma will decide their fate but it will not change my attitude.