You know, I have sort have been this way myself. But usually you have to be really rude in the way your explaining something (work related) for me to do this. But I have for the longest time in life said some of the dumbest things in retort to other things friends were doing that was dumb. It cost me friends, make work rough and is the main reason I am seeing a psychologist these days. Even as a personal battle I would sway like a tree in a breeze and the day I swayed the wrong way was the day something stressful or questionable would come up and I would say the "wrong thing". What really sucks is not seeing the words as being inappropriate at the time. They just come out and I think nothing of it until weeks later (and that's even recall the event at all). I really hope all the best in your efforts and hopefully we can all work towards kindness and well chosen words.