Santosha means contentment. It’s the sweet, comfortable spot between the two extremes of losing our minds with excitement and hitting the depths of despair.
Clearly, their are outside events that could bump us to one of those extremes. In life, great things happen; terrible things happen. When they do, we honor whatever feelings come up at the time, and we take appropriate action.
Santosha is more a state you want to maintain in daily life. It keeps you off the emotional roller coaster of dramatic extremes that can drain your energy. It puts you in a state of equilibrium that allows for steady energy, clear thinking, access to your intuition, and greater authenticity. Cultivating a sense of contentment with what you have and who you are has great side effects, too: it reduces the need for retail therapy, shopping and accumulating as a soothing measure.
For more on how you can develop Santosha, contentment, see Day 15 of Yoga Mind: Journey Beyond the Physical.