Pedophilia is very complex and there are different forms and causes, etc. Some understand very well how wrong it is.. and there are some who may not.

Some people who fit the definition of a pedophilia may never act on it. (Many would argue they are not pedophiles I'm sure). Acting on it can become a compulsion which then becomes an addiction. Which seems to be the case in the original post.

I'm not taking more time to explain. There's lots of information at anyone's fingertips using Google.
Here's a fine article on the subject.

pedophilia