This moment that we're sitting in right now, will not last forever.
A few of my students struggle with the concept of time moving forward. They act on the understanding that whatever moment is filling their lives that second, will be what fills the rest of their days.
I sit with J, listening to their screams and cries, jagged breaths and messy sobs, realizing that I too might have the same reaction if I believed that this little moment of failure, this moment of not being first, of not being rewarded, of "whoops, that's not the right answer..." would last forever. Condemnation, no matter how insignificant if i lasts a second, is crushing if the end is nowhere in sight.
So I sit, and we practice breathing deep "starfish" breaths, filling our brains with oxygen to manually relax our bodies (both of which are shot through and shaking from the screaming) and get ready to take our next tiny steps forward...just like that same starfish.
The trick is to remember to look back every once in a while to remind yourself that yes, those other forever-moments? They have passed. And these next ones will to. And soon, you'll be over this boulder and on to the next.