Depends on people and context and ppl can have lapses of judgement and be stupid. I called my husband a "son of a bitch" before while we were laughing (he was probably teasing me). In front of his mom. She seemed amused by it even though it dawned on me almost immediately. No harm done though in this case. OP did say he does jokes like that with ppl he's comfortable with, friend clearly isn't seeing eye to eye there. I call my best friend a bitch all the time (she does the same) and we laugh about it, every person has their limit and boundaries and those weren't established between OP & his friend