There are some things that are considered beyond the pale to some people. I personally know a pedephile who molested my niece when she was 8 yrs old. (She never told until many years later so he was never prosecuted.) To this day he makes excuses for what he did - he was young too (16), he was molested himself, it was just play that went "a little" too far. If he ever completely took responsibility & said "I was wrong" without any qualifiers it would be much easier not to view him as a monster.
He sounds like a typical child molester - making excuses, justifying the behavior...it's all about them.
"Marge, if you're going to get mad at me every time I do something stupid, then I guess I'm just going to have to stop doing stupid things!" - Homer Simpson in the Mr. Plow episode