Unfortunately, it really exists and that is the reality when it comes to gambling - many people lose control of themselves and got fall into addiction.
There's the psychological effect of gambling and that makes us think that we're still in control but in reality, we've already lost our control. Thus, gamblers that are aware they're still in control, it's just a matter of few bets then they'll be tilted and going to have the mistake in their lives just like the others that are thinking of the same thing.
And you are right, many families got broken due to such issues and sometimes committed crimes. But still, we can stop gambling if we really wanted and committed to doing it, yet it will take time to heal and to finally forget gambling.
In my country, gambling is almost everywhere. I've got friends and families that have broken relationships because of their uncontrollable gambling addiction. They sell almost every stuff that they've got even if that's the only thing they own like their few appliances. They will only stop if they've been shouted that they're unlucky and they need to take a rest and nothing is left anymore.