S.W.
Hi L.,
He needs coping skills. Sometimes it's hard for us to remember being that age and having the fears wash over like a tidal wave. Try to cast back to when you were 8. I know when I was I had to cross the hallway to get from my room to the bathroom so those night time potty breaks were especially difficult. Mom gave me a flashlight and in a short time with that tool things got easier and easier as I gained confidence. This is just one example, I won't bore anyone with more.
Anyway, when my DS was about that age some dingus (sp) introduced him to slenderman. OMG!!!!!!!!!! Talk about fear and anxiety....Stopping short of boxing the other kids ears which would have created a whole other host of issues, we worked together on developing a coping strategy. We implemented it and, while it did take some time, he slowly emerged from this anxiety.
I know I sound like I'm oversimplifying this. I think it's important that you are taking this seriously and I also agree with the posts below that meeting with a therapist is an excellent idea and can only help him and you develop his confidence and find some coping techniques. :-) S.