Where there is love there won't be room for hiding anything from your partner.
Are you sure? Although, I do not see any reason to hide your gambling activities from your wife but when it comes to life generally, there could be a good reason to hide something from your wife. Someone that is receiving a salary of $1000 weekly has a reason he told his wife he is only earning $350 weekly. Or there are people that will not let their wife know how much they are earning.
I don't understand why you don't trust your wife and hide your income or assets from her. If you don't trust her, why did you marry her? But for me, my gambling habits or anything that happens in my life, I share with my wife, especially money related issues. Simply because I don't want to create distance and suspicion in the relationship between husband and wife, that only causes the family to break up soon without bringing any benefits.
Have you ever thought about how your wife would feel if she knew you didn't trust her and how you would feel if your wife hid those things from you? To me, that is not love, not a happy family worth living in.