Bitcoin is crashing because it was irrational for it to be anywhere remotely close to as high as it was in the first place. Bitcoin is really just a speculative commodity, and not a currency at all. It can't be used as a currency because of its volatility, yet people try to value it as if it were a currency.

This crash is 100% normal, it should not surprise anyone, and it is only beginning, with plenty more room to fall. Bitcoin does this over and over again. It will crash down and stabilize for a while (maybe a couple years) and then have another bubble where it crushes previous all time highs.

Basically you only want to buy bitcoin when it is boring to buy bitcoin... and even then, it's still an extremely risky investment.