I've literally seen this happen right in front of my eyes to some of my friends. They brag all about how they pulled an all-nighter on Friday night, then woke up the next afternoon and worked all through the weekend.
Then they also have an angry outburst at me for the smallest, silliest and stupidest reasons. They eat trash, mostly impulsivey, are pepetually on edge, so you've always gotta watch your words, and can't take an iota of criticism without taking things personally and exploding like a volcano all over the place.
After encountering so many overworked people with zero social skills, I've learnt to keep away from them all together and it is my strict policy now to never hang out with workaholics.