You need to treat bitcoin as a commodity, rather than a currency. I'm not sure where it's long term future lies, but think that as the full 21 million bitcoins are mined it will be pursued out of rarity - like gold. People will die, wallets will be lost to all kinds of accidents, and the amount of available bitcoin will decrease over time - but this will take another 5-10 years of volatility at least. It has hung on for a long time, but grew massively relatively early on.