First of all i think that the problem is that gambling addicts don`t know maths good. Also they don`t know hidden rules of the game(like RTP).
As for me the main help is to show their win chances of some simple examples. Something like "In this round of lottery there are 500.000 participants. In your city there 100.000 citizens. Your chances to win jackpot5 time  less to become a major". As the result they can understand that their goal is just a dream and stop the game themselves. Anyway the first step to stop is to understand that they break their life with such dreams.

PS. I`m not gambling man and don`t even understand what it means to be seriously addicted, so maybe i`m mistaken.