Thier is nothing strange about this feeling. If you're not winning, it's almost impossible for you to be happy about it and regardless of how good you are in keeping situations to yourself, you can't cope by not showing it to people around you.
What's necessary is just the ability to managing your temper at that instance so it doesn't become a serious issue that could lead you to transfering aggression on someone else. Most of this unnoticed impolse needs you to control them as the boss of your life and so you need to basically tell yourself that if you've lost, that's just it, no one should have to be molested for that reason, deal with the loss naturedly and know that what has happen has actually happened and Thier is absolutely nothing you can do about it.
The difference in losses also matters, and the reason for telling gamblers to wager what they're able to lose. Developing a behavioral change only explains that the gambler wagers a substantial amount of money, that got him thinking about why he's lost such an amount, which could have been used to settle other troubles. However, anger management as you said, helps in bypassing this type of attitude. The gambler also needs some time to handle his mood swing after losing money, gambling.
It's all a gradual process to heal or change, but the trouble doesn't end there, due to the pains the gambler has inflicted on his loved ones. The end result still boils down to bullied child or person getting depressed or emotionally unstable. That's the most important need to take gambling gradually. The cause of the problem can be solved, but the damages it caused, could stay forever. It's embarrassing, getting angered over the result we get while gambling to an extent of harming somebody else. The gambler needs a serious help and shouldn't neglect it.