The financial markets and trading offer the ability to earn huge profits and huge losses, risk-management and a responsible approach making sure that you truly understand everything you are doing is key to success in this fun, exciting and potentially very rewarding industry. Spend your time researching and learning as much as you can, learn about risk-management and try to always see what other people cannot - all these things motivates and develop me to remain in the trading.
Searching and learning are not enough to make a change to our mindset when we are already been disturb by our emotions brought into weakening our trust and confidence in Bitcoin. What makes someone able to hold their holdings even seeing the declining scheme is because of having faith in their investment, they're believing that after this struggle, it turns into their favor back. OP didn't have such faith, a reason why he becomes worried and weaken his hand and sell.
Maybe we need to learn how to manage emotions before trying to hold any coins because that will not be easy to see the price moves and sometimes, the price can make us panic.
If we have a strong heart to see how the market moves, that will not disturb us to hold the coin for more, but we will see a chance to buy more at a low price.
The investor will not just stay calm if they see the price is down, but they also prepare the other money to buy more amount to increase their coin amount bigger.
That will give them more profit in the future, especially if the price can jump to the highest price shortly.