The best thing to do with GAL is to do something PHYSICALLY active. This gets your mind out of that imaginary place where those images show up and into the place where your mind has to work t control your body. If you take up tennis or something you will be too busy to think...
Just keep physically active, you'll get through them. They DO fade away and happen less frequently over time. In the beginning its all day long. After a week or two the images appear much less frequently.