Yeah, gambling absolutely has the capacity to break up a marriage and or family, I have witness this happen myself, it happened to my direct friend whom we both were working in the company here in my country before we both got married, my friend was a gambling addict which I wasn't aware of, I knew he was into gambling but I never knew he was addicted, I got to find out he was addicted only after he got married, when ever he was out of money to use or spend on gambling, he would start searching his wife's things and take her money and squander it on gambling.
At a point, the girl became fade and she took their only child, a boy and left the marriage, this is was way back 2017 and till date, they are not yet back together as I learnt since I myself later relocated to another city.
And speaking of disclosing our gambling activities to our partners, well, for me, I do not buy the idea but it depends on the type of gambler the man is anyway.