Making up bad scenarios in your head.

I am wondering if any of you make up scenarios in your head to almost "test" your reaction in order to prove to yourself that you would never act on your thoughts. For instance, I am very close with my family and I will make up a scenario in my head (usually having to do with them being physically injured or hurt) to see what my reaction to that scenario is. I don't know how to explain what happens, other than going through these fictitious scenarios and paying attention to how I emotionally react to these situations in order to temporarily relieve symptoms.