I don't know how someone can stay calmed when dump starts, and all of a sudden you are bombarded from every source you watching with terrible news.. Im mediocre trader still learning, but how can you know that that is not 500$ dump or even lower? Everything looked like going back to beginning!
it is a valid concern and I am not pretending that I don't have it. but it is all about chances of different things to happen. and also it is the experience of knowing what can affect bitcoin price in what way and by how much, and then is it really serious or temporary dump to get cheaper coins.
for example when you hear bitfinex exchange is hacked, that news is obviously a dump chance to buy cheaper coins because it has nothing to do with bitcoin and its adoption and the price rise. so obviously it is temporary.
when you hear Mark Hearn spread some FUD because he is leaving bitcoin and going to work other places to make money, you know it is good chance to buy low price coins (I think it was $400)
or the newest one about the China and the regulations! it is obvious that the news is telling something when reality is something else, specially when you look at Chinese volume in other places such as localbitcoins that have gone up a lot.
and so many different things. add to it the fact that there is very limited supply of bitcoin and there are lots of people in the world who want or will want to buy bitcoin at some point, and you get the future possible price in long term.
https://bitcointalksearch.org/topic/1-in-a-million-updated-for-2018-6-1790863