In the past few days, the crypto market has plummeted. Many coins are down by more than 30% from their ATH which were usually achieved in just the past two weeks.
Now I'm certainly bummed to see the value of my portfolio drop like a rock. However, such is the nature of the volatile cryptocurrency markets. I still believe that certain coins will increase in the long-run. I emphasize "long-run" because you have to look at the bigger picture and not be consumed by market fluctuations day-to-day, or even week-to-week.
This image is currently on the front page of /r/cryptocurrency. It shows what happens when Bitcoin had historically moved below its 100-day trailing average. As you can see, these downturns look merely like blips in the timespan of two to three years. In fact, if you truly believe in your portfolio, you should consider doubling down on your holdings. After all, the market is on discount. Consider this a January special sale. "Buy Bitcoin at a low, low price of $10000! ETH at $800, limited time only! 2-for-$1 special on XLM!"
As for me, I will be heavily considering buying more of the coins I'm currently hodling, and I will be considering new coins to add to my portfolio, too. I'm in it for the long-term.