Keep calm, and have a coffee, said me a trader when lemhan and half financial world collapsed in 2008. He said "Don't follow your ideas, follow the market! Remember that as the world goes, there will always be something to eat ".
Nothing could be more true!
If you are a trader, a real trader, you will make your fortune when the market goes down and others sell! Short all & buy at discount. The sales time is starting
Checking the history of btc since 2016 and 2017, a crash like this is normal, actually this crash is lower than 2016 and 2017, if this doesn't make you buy and invest, I don't know what will.