We have to realize that in life the way we treat people will be the way that people in life treat us as well. As the bible states we must "Do unto others as we would do to ourselves." Meaning we have to treat others the way that we want to be treated at all times, in order to receive the treatment we deserve. Treat others with kindness and compassion.
Never let the turmoil in your life that you may be going through determine the way that you treat someone. Remember in every interaction with people that you everything you dish out will be returned in some kind of way to you. Dish out the kind of positive energy that you want to receive, and remember that all the seeds you sow will produce a fruit, whether that be a good product or a bad product!