If you weren't inclined to sell at $19k, then you shouldn't be inclined to sell now.

Just buy more at intervals on the way down. You'll eventually be glad you did.

Or you can wait for a trend reversal, but you may be waiting a long time, and then when it turns you'll just be chasing it back up.

Who here doubts that Bitcoin will be at $50k by 2020? I don't.