I think that this has happened to all of us at some point, I've seen some friends who have spent a lot of money in physical casinos, it has happened to me in online casinos and the fault has been because I have not been able to contain my emotions, one says that one can control one's emotions, but it is difficult to be playing and controlling that game without losing control, that is the difficult part, it's easy to say it here, what I think when I play is that the money that I am going to spend will not be recovered so quickly since it requires a lot of effort, that is what can hold me back sometimes.
Usually while gambling we should expect the unexpected from gambling and anything could happen. The most important while gambling should be that whatever amount we are using to gamble should be the amount that would never be that effective to us when lose, became most people so much focused on using amount that are big so that they would also win something very big as well, but it doesn't work that way. Any one who understood how the gambling works would never be that angry whenever they loses their money while gambling and of course people are so much focused on the winning that is involved while gambling.
There is nothing wrong gambling with big amount of money as long as it won't affect you if it doesn't work as plan or if you lost, there are people who actually gamble with what they can't afford to loss properly to win big as you said, winning in gambling is never certain it is practically a game of luck and shouldn't be gamble with money for family up keep in other no get your depressed after lost because you choose to gamble with what you can't let go.