John Preston, PsyD, ABPP did a training on “The Habits of Stress-Resilient People” last month. Putting my two cents in the mix, you can develop stress-resiliency by:

acknowledging that pain and suffering are a part of life, rather than an exception - if you live long enough, and sometimes, you don't even have to live that long, you know that crap will hit the fan
choosing to be with uncomfortable feelings - as unpleasant as they might be, difficult feelings will be there. Feel them rather than hide from them; they do come and go
having a good cry – according to biochemist and “tear expert” Dr. William Frey, tears contain stress hormones that are excreted from the body through crying
taking things in, moment-by-moment - fight the tendency to operate on auto-pilot
recirculating moments of joy – everyday, train your brain to notice the things that have gone well that day
focusing on doing what works – do what is most effective in the moment, rather than dwelling on what's fair, unfair, should, should not, etc
living a valued life – What matters to you? What do you want to live for? Doing those things will bring you vitality and meaning even when life gets tough

Thoughts? Would love to hear them! Need help developing these habits? I'm here!