The volatile nature of cryptocurrency is why it's never an ideal investment, lack of regulation place an important role in the upwards and downwards movement of bitcoin or other cryptocurrencies. Bitcoin can only attain mass adoption when regulation comes along and this will be when the price becomes stable.
What? Don't you know volatility is a trader's best friend. It is how they profit. If the price is just flat from weeks on end, no trader will make money. Regulation has nothing to do with mass adoption. In fact, most technologies get massively adopted first before regulation comes.