Gambling Addiction & Recovery Support Group
Compulsive gambling is an urge or addiction to gamble despite harmful negative consequences or a desire to stop. A preferred term among many professionals is problem gambling, as few people described by the term experience true compulsions in the clinical sense of the word. Problem gambling often is defined by whether harm is experienced by the gambler or others rather...

My guess is that while you say you did not have the normal triggers or stressors, you likely had some trigger, you just did not notice. Sometimes the trigger is having time, money and no plan. (One of my dangerous situations.)
You may want to check with your counselor about couples or family counseling and see if your family would be willing to participate. I suggest you go to a few sessions and give it an honest college try doing any homework between sessions your counselor asks you to do before breaching the couples/family counseling idea.
You can get through this.
2.) Does your health insurance cover in-house rehab services? Something to consider.
3.) Get a payee. Someone who receives all of your paychecks and has access to all of your accounts, who pays you only an allowance.
4.) Self-ban from all casinos in your state, if the program is available.
5.) Don't worry about your marriage for now. The gambling addiction is about your relationship with yourself. You need to concentrate on getting you better before you can even start to repair your relationship.