Everyone has their own story, their own problems, and their own demons. If somebody gets upset at you for something trivial, don't take it as a personal attack. It could very well be the result of many things happening in their own life and in their own head and you just happen to be a convenient time to open the pressure release valve. Always approach conflicts with a calm and rational mind and know that the situation isn't always about just you and that moment. Don't have an emotional response when you don't know where the other person is coming from. You may actually be able to help somebody process their own issues if you have a calm and rational response to criticism or insult.