When working on making progress it is important to guard against ourselves. When life throws you a curve or someone chews you out, the first inclination of a human being is to look outward for the cause. Epictetus (Handbook 48) counsels that this is the path of the uneducated person; a philosopher will do the opposite.
 The condition and character of the uneducated person is this: they never look for benefit or harm to come from themselves, but from external things. The condition and character of the philosopher is this: they look for every benefit and harm to come from themselves.  The signs that someone is making progress are these: they blame no one, they praise no one, they find fault with no one, they accuse no one, they never say anything of themselves as though they amount to something or know anything. When they are impeded or hindered, they blame themselves. If someone praises them, they laugh inwardly at the person who praises them, and if anyone censures them, they make no defence. They go about as if they were sick, cautious not to disturb what is healing before they are fully recovered.  They have rid themselves of all desires, and have transferred their aversion to only those things contrary to nature that are in our power. They have no strong preferences in regard to anything. If they appear foolish or ignorant, they do not care. In a word, they keep guard over themselves as though they are their own enemy lying in wait.
Recently, I had an incident with a friend of mine from school. I had invited him to a hash event, where many vulgar songs are sung. One of the songs offended him sufficiently that he left early and hasn't spoken with me since. My initial reaction was to apologize for offending him, but as time went on, I found more and more reasons to blame him. This is a mistake on my part.
It's like this: If he was oversensitive, so be it. I have no control over that, I only have control over my own actions. It does me no good to speculate as to his motivations or resent him for his actions. The only beneficial act I can take is to examine my own actions.