It’s important to take responsibility for what you say and do.  But it is equally important to remember that it is not always about you.  So if someone treats you badly, or ignores you, or does anything that makes you feel that you are less than, go ahead and take a look at what you said or did and make sure that you are comfortable with it.  And also realize that the other person may be having a bad day, or may have just gotten some bad news, or maybe just isn’t in the mood for anything right now.  It may have very little, or even nothing, to do with you.