I recently lost a dear friend of mine and while I can say I thought I knew myself, I lashed out and lost myself. In hindsight, it was mostly my fault and I lost a great friend on my own. In my honest and blatant opinion, many of the issues my peers (and especially myself) deal with are because we do not know how to handle certain situations with others. This can have disastrous effects.
You might ask yourself "why?". Why should we should know ourselves? It is a legitimate question: we should know how to react because life happens, and we cannot control everything and neither will we always get our desired response. Our boss will not always be our best friend, and we will not have humble and brilliantly social friends. There will be awkward situations and asinine reactions from appalling humans. We have to learn how to react the right way in all of these situations because these events will eventually happen.
How do we go about this? If it is a message, do not reply immediately; sleep on it and/or take your time. If it's in person, maintain respect for them even if they offend you, and reply without anger. Walk away if you must, and say you will talk to them later. The point is we cannot act on impulse because people never react well to it. Some will respond with anger, and others will mock you, laugh and smile, and that will only enrage twofold. It will rarely end well for you if we are impulsive and aggressive. Trust.
"Life is 10 percent what happens to you, and 90 percent how you respond to it." - Charles Swindoll
This cannot ring more true. Learn how to handle the worst situations and the worst people, and you will learn to appreciate those who treat you well. Pushing away the people we love will only end in being alone; no matter what you may think, no one wants to be alone, and no one wants to be around others that make us feel alone.