Push through the burn for a few extra reps. Do an extra cycle of HIIT. Run an unintended 1/2 mile. Turn around as you're about to leave the gym and bang out one last set. It's amazing how satisfying work that's unexpected, unplanned, or unintended can be. Try it out.
This is hard to remember as an entrepreneur, but so true. "Comparison is the Thief of Joy" -- Theodore Roosevelt. How do you maintain a competitive edge without comparing? You can be aware of what others are doing, but focusing on your own efforts, rather than constantly comparing yourself to others, is where the joy will be found.
There are many people who look out for other people. Surprisingly, younger people don't get that people in authority are willing to help and are in alignment to advance other people with good intentions.