Gambling with my future

On Saturday, I discovered my partner of 9 years has been gambling again. It was thousands and more than he even earns in a year. He didn't readily offer up the information, I came across an app that popped up on the iPad that had linked to his phone. He's done this before - this is the 3rd time. The difference is now I am 8 weeks pregnant!!! I am scared and don't know what to do. I will never be able to trust him and will have to baby sit his money and be constantly vigilant, maybe for the rest of our lives together as the last time, when I stopped checking up, he went straight back to it. Has anyone had a similar experience? I feel lost and don't know what to do for the best. I trusted him and I feel like a total idiot!