The fact this concerns you is the most important part of your email. The imagery on the site you mentioned, others like it, and even mainstream news can have secondary effects from watching it. Whenever people have been pulled into a compulsive need to watch a specific type of material (porn, violence, bad news items, etc.) the concern becomes understanding more about what is beneath the need. The fact that you needed to do this during school means that it is being given more of a focus in your life than it should. One way to determine the strength of an obsessive-compulsive behavior is to stay completely away from the site or anything like it for 30 days. See how this feels and if it is still such a necessary thing. If you find it hard or impossible to stay away, I would encourage you to talk with a therapist about it.