I'm so sick of it!

My husband is constantly spending his credit card money when I've been trying the last 11 months to pay it off! He's been using it to pay for games. He has maxed it out a dozen and one times. We put about 600 towards it every month and it still hasn't left the 10000 range in 3 months! The only reason I got under 10000 before was because he was on deployment for 7 months. I recently told him that it'll ruin our marriage if he keeps doing it, and I really thought I got through to him because he went a whole week without spending anything on a game. He even gave me his credit card so he didn't spend it. But I just went on it and he spent almost 100 dollars on games again! I know I should stick through it and try and help him but I honestly think it's a lost cause...