She had just a hard, hard life. One thing that I haven't seen mentioned yet is how when she was first a Guess? girl, she almost always spoke out against sex abuse in children, and trying to get people to be more aware. It was after her first few ads ran and were super popular that the "ditzy" Anna was seen more often than not. She stated numerous times that her sexual abuse as a child was something that she NEVER got over, that she did not have a positive role model in her life, neither male or female, and there was not one person she could count on until she had her son, Daniel.
I don't know that much about Howard Stern, but I can lip-read, and there were NUMEROUS times on her E! show where he would be telling her, "you don't have to act like this", or "why are you pretending to be like this" and things to that effect. I know he told friends of hers that he was having the committment ceremony to try and cheer her up.