If the A invests $1000 in bitcoin, then the next day the price of bitcoin drops dramatically and the A loses $1000, which makes me curious, where does the $1000 A money go?
You already said th $1000 is an investment. so it is governed by principle of markets.
News made the phrases like "lost billion dollars" to make you believe that really a worth of billion dollars wasted?
It is never real Dollars. It is the potential that you lost.
For ex. I have a house that I sell it now for $1000 but after one month if I am getting offers for $800 only , so according to investor /News I will lose $200 but in reality I just lose the only potential $200 but no actual loss.