I was taught ever since I was a child to treat everyone with love and respect. I was taught to never look at anyone with disdain, regardless of anything they have done to me, and regardless of how different their lifestyle is from mine. At times this was difficult, as it continues to be, but practicing a loving lifestyle is not only the mature way to live, but also the right way. Your moral compass should always point in a direction that encourages patience and regard for every single person you cross paths with in life.
Often times, the first impression we have of someone, simply by looking at them, is a negative one. Rather than seeing someone as a human being, filled with life and a unique story, we choose to judge their outward appearance with one single glance. Rather than taking the time to understand their motives and goals, we create a scenario in our head that is typically far from accurate. However, we need to practice love and respect. Treat others exactly how you want to be treated, and reciprocate affection everywhere you go, and with everyone you meet.
Throw away all disdain.
Live with love and respect.