YOU TEACH PEOPLE HOW TO TREAT YOU

It is a common saying that we are taught at an early age, treat others how we want to be treated.  This was drilled into my brother and I until it became our normal.  To treat anybody any other way, I cannot even conceive it.  This is just how I am.  It is not being fake nor is it being forced, I genuinely am the way I want people to be around me.
As an adult I have taken it a step further, in that I teach people how to treat me.  We all encounter people that may be rude, forceful, or just not nice.  We do not however have to tolerate such behavior.  People are like children, in that they will try you, to see what is acceptable to you.  Once you allow a behavior, especially repeatedly, it becomes a norm. 
You however have a choice and a right to set the rules and boundaries involved in dealing with you in any capacity.  If you dislike a certain behavior and you address it, either the person will reframe from it or they will continue it.  It depends on how they relate to you, or better yet, how they respect you.  If it continues, you have the choice to remove yourself.  If it stops, you have set a boundary.  This person then knows how you want to be treated.
I tell everyone, people will treat you how you teach them to treat you.  If you lay out what you will and won't accept, and refuse to budge, if that person likes you, they will conform to you.