The guy is human and can make mistake. And clearly he made a mistake to break his longtime marriage for a love fling he had with another and more younger woman. Mel Gibson has a history of racial remarks and it doesn't come as a surprise he once again did it. Thats why people are believing it, and Passion of Christ movie it's said by some jewish organization that promotes anti semitism (I believe its relative. And that its arguable) But he needs to get himself in check because he has lost his guidance in life and needs to refocus and get himself back to where he is supposed to be.
Mel Gibson is a celebrity and people will be hard on celebrities that mess up. Tom Cruise, Tiger Woods, Mel Gibson, etc etc. People exacerbate some stuff that really shouldnt matter like tom cruise behavior. But sometimes tough stuffs like Woods and Gibson are really issues that affect the people closest to him and cause a detriment in mood that can spiral into something even worst.