- Monitor your emotional state and take breaks. Also accept that it is normal to be emotionally affected by people writing/saying terrible things to you. There

- Monitor your emotional state and take breaks. Also accept that it is normal to be emotionally affected by people writing/saying terrible things to you. There is nothing wrong with you. - Take a systems view. This helps you remember that you and your product are a very small part of that person's life and to remember all the variables that aren't you that might be making the person unpleasant. - Since you're a solo dev and therefore working for yourself, I presume: It's perfectly acceptable for you to have standards for how you're addressed. One of the benefits to working this way is the ability to say: "I am not comfortable working with someone who is speaking to me this way."