This is how some of us think in 2013 and those that were able to invest in bitcoin without considering if they investments is going to loose has make money when bitcoin get back on it feet in 2016 and 2017. I don't think that fear has ever help any investors rather it has been been creating regret for traders. Trading and investing into cryptocurrencies is a higher risk venture and only the enthusiasts and confident in what you are investing in is what will help us in this market. I believe that no matter amount of price rate that you buy bitcoin or others coins if you can hold you are going to sell at profits one day.
I've learnt not to be emotionally vested in anything crypto. Best thing is to study the tech objectively, analyse the capabilities of the team, and project possible use cases whatever crypto I'm investing in will likely have in the near future