Thankfully, I sleep like a log irrespective of share prices.
The only instance I didn't was the night of the '87 crash - then I slept like a baby; woke up every half hour crying.
Something else worth remembering, it's usually only the small, mug punters looking to make 1000% in 5 minutes. Most mature investors have more realistic expectations. For example, the average investor would be thrilled with a 20-30% return per annum, especially if a benchmark index is returning less.
Personally, I'm an asymmetric investor, hoping to make hundreds or thousands of percent returns, however I don't expect to make those sorts of returns overnight.
There are many investors who'd be thrilled to buy at $4 and hold for a year or 2 to see $5-6.
Not everyone is looking to hit it out of the ballpark all the time.