That is instructive and very important but difficult to do and this is the reason that some gamblers will resort to drinking when they lose. Usually, to forget that you have lost a potential huge winning especially narrowly, you will need to go out of your comfort zone or avoid staying lonely because of thinking about the loses and the money involved. Therefore, a gambler needs discipline to take certain decisions whether at the time of loses and when you win. For example, it is discipline that will make you take a break after a losing streak and also it is discipline that will make you caution yourself from over spending when you win.
Such control is needed as you don't want to keep regretting your actions, there are gamblers who become more aggressive when losing their bets and instead of quitting they did choose to engage more and add more money, only to realize that at the end of the day most the outcome also a failed attempts to recover as they play with aggressions they don't have any clear views just to put their and hoping that luck will permits them to win and recover or win some from the next try that they do.