6. Don’t bad-mouth his family and friends.
“I criticized his brother who borrowed a suitcase from me but returned it empty. He got teed off by that.” Others said, “I called his friend a nerd and he got upset.” Tread carefully when expressing opinions about his friends and family. Most of the time, they are unwelcome. Still, if you feel terribly offended by his mom’s comment (for example, “I find Southern foods too greasy”), it may not be a bad idea to be honest with him.