Most likely people will lose their trust in you and the last person who will leave you is your partner because she knows everything about you when things don't get well and it gets worse day by day, she will leave you for her sake. I'm not gonna lie but I know a person who truly supported her boyfriend throughout his worst time but sadly he took advantage of her and asked her to provide him some money until the girl ran out of choices and chose to break out with him because she no longer has the ability to provide for him and he is not getting well rather he is getting worse and asking more money to suffice his addiction.
I think the topic is not limited to relationship of spouse or girlfriend but seems like you are talking about a situation when you have a real partner who understands you better and love you for who you are find out in your back that you gamble and from the beginning you didn't inform them. It's really sad when you find the truth later because I do see it as lack of trust and anything that comes from that same mouth in the future will be doubt to me isntead been accepted as the truth, it's always good to come clean and straight, if your partner can manage you, they will accept you for who you are and if they will not, they will let you know before the relationship go deeper.
Just like I saw some months ago in a thread where a young boy won a million from gambling but the parent refuse to accept the amount their son gave them because their beliefs is against it and they weren't happy about the source of his money, this is how the people that loves you lost trust in you when you gamble but in the real sense, they think you are just an average guy who do average things.
However, let's say you are a hard die fan of gambling with the addiction but you pretend to your partner that you don't gamble and they later find out that you do that and maybe on that same day, you won a life changing amount of money, even if they feel disappointed and angry for pretending, they will only be angry for a short time, the money under your possession will make them forget that reaction quickly, that's the power of money and how it transform judgement quickly without doing anything. This is to show you how some people loves money than anything in this life.
It does hurt the hurt that comes from discovering a hidden truth. When discovered rather than confessed, gambling is a heavy burden. It stings, a betrayal sting. Having said that, I do think it's important to be forthright and honest from the get-go. If I were in that situation, I would prefer the painful truth over a sugar-coated lie any day. The youngster and his parents' experience shows the consequences of gambling, even if they win. I cannot emphasize enough how much trust is lost in these kinds of circumstances, and it is not easy to rebuild
Though, I believe that money has two sides. While it might seem to provide short-term solutions, what about long-term effects? It's not a solution, particularly when it comes to trust and emotional issues. Relationships and trust are more valuable than all the wealth, in my opinion