Stomach Flattening?

No it is not possible without cardio. You need to burn more calories in order to lose that fat. It seems like you've tried a lot of different exercises. Maybe taking a cl or walking/jogging with a friend will help you stick to it. Swimming, rock climbing, and biking are all fun too. Just keep trying new and exciting things, and add as much variety as possible. Try to see exercise as a way of life, and recognize that it makes you look and feel better, instead of as a chore.