Challenge and peaceful places or empowering social/solitary situations. I've found that if I channel my frustration toward my goals I can use it to drive me to become more active and attentive. I sometimes envision myself and the world as two separate entities and when it presses me with problems I think "I haven't shown you my best yet, you fucker" and so I imagine I'm fighting with it.
If I'm trying something and it fails often times I will smile and try to do it even better. You'll often see me smiling after I've broken expensive equipment or made social/public mistakes, this means either I entered my tranquil cold fury focus mode or my happy challenge-loving mode.
For as long as I'm physically healthy I'm optimistic about my life.
That said I have complete attitude of acceptance for my limits and for the inevitability of my decay and demise. There were and will be moments when I can't perform or fail at something and there are boundaries beyond which I can't hope to leap. Despite this I consciously harbor an attitude for ignoring limits and own weaknesses so that I can improve and give more out of myself than I believed I could, even if it may later prove to be impossible, impossibilities should be ignored and tested repeatedly, as long as one wills it.
The worst times for me are when the circumstances restrict me from regaining my composure, disable my clear thinking and ability to apply it to reality, usually in a way of my mistakes and ineptitude or poisonous people in my life, or obligations/sudden accidents of some kind in short succession. I tend to then feel depressed from time to time, but it's chemical, I'm aware the depression/exhaustion doesn't help the situation so I live alongside it doing my own thing less efficiently due to low spirits, waiting till it passes.
I think at those times I most strongly benefit from positive emotional experiences, I try to wake my feelings up from the forced encasement so that they restore vitality to my mind. It can come about by positive interaction with people, indulging my sadness or anger and then using it to restart my sense of calm and direction. Melancholy, anger and sadness have a positive side when I can use them to boost my sensitivity and curiosity about the world outside of me. Really, all of my problems have always been in my head, even when the circumstances that were a significant factor behind causing or solving them were external I had to look to improve those external and internal variables from inside first.
Possibly it can be useful to think about negative factors as subtractive maluses that slowly take away from the individual's stamina, it's not critical until the negatives outweigh the positives and the natural regenerative rate of the mind-body. Then slowly the most demanding functions begin to shut down, things like ability to interact with others, to perform inspired work, to experience emotions or understand subtle cues about situations and dangers tend to go down first as they require the most creativity and available energy. After those go down one can't rely on them to regenerate the already withered state and it catches one in a prison in a way.