followed with ‘I wasn’t aware is so important to you. I didn’t want to insult you and if you felt so, I apologize. The word fuck is one I use very often, but I’ll try to control myself around you’
Note I didn’t insult the coworker (no fuck you or fuck off), but simply said ‘fuck’ out loud due to a job error.
Also, don’t say, “I wasn’t aware it was so important to you.” That’s definitely a trigger phrase.
Try, “Thank you for letting me know this is important for you,” (or “how you feel”) instead.
Not too shabby!