Personally, and this comes as a bartender, a teacher, a coach, and a game official, I respect everyone until I have a reason not to. I don’t trust you, but I respect you.

I try to treat everyone with respect. You can be unkind to me, you can disagree with how I live my life or the person I am, and I will still use manners. I will still address you respectfully, I will still treat you as a person. Because it doesn't matter how rude or disrespectful someone is to me. If I return that energy then they're winning that battle. And even if they're rude, maturity is being the bigger person, and showing others love no matter how little love they show you.