Yeah, trading cryptocurrency, gambling, playing games, and some other things can sometimes just compel one to get emotionally attached. For instance, if you are a trader trading with $100 in capital and you experience losses to the extent that you are now left with $20, if you allow your emotions to take play, you might end up losing it all, but if you have a good skill at controlling your emotions, you should know that with such a loss, you should take a break and try again later or the next day. The same applies to gambling. The advice is for a trader to always not allow their emotions to control them while they are trading.
In trading or gambling, there are good and bad days. There's days when your star is shining and you're winning, making gains and all that, you need to remove your profits from the platform to safeguard them from being lost in the events of tables turning round.
Also there are bad days, like days you lose as though losing is your calling. For example, like you're gambling with $100 as you mentioned above and you've lost like 50% of your capital, your mind should be alert to avoid going further for the day, and even if you go further and somehow loose up to 70%. You should take a serious break as that day isn't going in your favor, if you blindly continue, you might loose everything and even deposit more out of desperation. Believe me, the possibility of losing all is very high because your star isn't shining that day at all.
In a nutshell, there are good and bad days, your ability to recognize bad days early enough and avoid the total mess it brings along is a testimony of your gambling discipline and high emotional control.