The highest skill is resilience. If you can be cheerful and relaxed while you're losing everything, you've attained resilience.
Part of resilience is taking things less personally, letting go of personal importance. When things go your way, it doesn't mean God loves you. When things don't go your way, it doesn't mean God hates you. Life's weird. Stuff happens. There doesn't have to be someone to blame. In fact, part of resilience is wishing well to those who've harmed you. Compassion isn't a business. If fact, it's not ethical to give compassion only if I get it. I don't have to stop behaving well just because someone else has.
Resilience is the opposite of self-pity, of being fussy. Wealth is no protection against the shocks life can hand you. The highest skill in life is balance: being adaptable, autonomous, cheerful and capable even when things go terribly wrong, being relaxed under pressure, accepting the nature of life while remaining active and creative, being hopeful even when you're losing everything. And without taking your stress out on those around you. Nobody likes being around a fussy person when things go wrong.
I'm not sure I need to try to make myself more adaptable. One of the functions of life is to make me more resilient. It is a good idea to try to stay alert and learn from experience. If something doesn't work, for example, I can try to figure out why not before I try it again.
On the other hand, I can work to overcome what stops me from being adaptable: self-pity. The way to do it is to develop the positive qualitites of detachment, sweetness, cleverness and patience. It helps to use death as an advisor, to abandon remorse and desperation, to live sparingly, and to disrupt the heavy routines of life in order to become free, fluid and unpredictable. Life is better when one is able to laugh, be patient, improvise, be creative, be joyful, and even be capable of controlled folly.
Here's a version of Resilience Skills you can download: