Will BTC ever come back up?

Maybe short-term with manipulation, long-term no, the currency is actually dead. More merchants accepted in 2010 than they do in 2017 due to various problems such as network fees and times.

If the currency is adopted, it will actually have a good value long-term. Currently only people trading currency is those doing illegal stuff or don't want PP refunds. And even they are moving to Monero because they are doing illegal shit and that's harder to track (still BTC/ETH is the gateway for all of them currently). Nobody else is using BTC at all as a currency, they are buying it as an investment for the last 7 years, not to actually use.