Really DMan? Who did Charles make the phone calls to? Was it necessary for the police to be called into investigate the phone call? Who did Charles place the blame on? Did Charles ever try and ruin the reputation of an innocent party, let alone take pleasure in such actions and brag about it?
It is one thing to be an apologist for Diana but could you at least provide some evidence for your counter claims.
Trying to reason with some people is a waste of time (especially when they claim that no one on this forum is critical of Charles).
There was an intelligent discussion upthread in which several people acknowledged that both parties were equally responsible for the breakdown of the marriage, but the public war, which deeply hurt William and Harry, was Diana's fault. Some posters will claim a false equivalency between Charles' interview and Diana's, but reasonable people see through that.
Charles never publicly criticized Diana, never asked him friends to criticize Diana, never harassed anyone, never used his sons as cover for his affair, and never betrayed anyone's privacy. He briefly tried to blame his decision to marry on the Queen and Prince Philip, but everyone makes mistakes.
Most importantly, he always kept the door open to Diana. Several people claim the relationship improved in the months before Diana's death, which was due to Charles's outreach. He was an excellent parent who, unlike Diana, always put William and Harry first while they were growing up.
Regarding the actual marriage, Diana suffered from serious mental health issues. It was in no way her fault and it is extremely difficult for someone who suffers from a mental health problem to admit it and get help. However, it is also very difficult for the family members. A high percentage of people who suffer from bulimia are divorced. There are strategies to constructively communicate with someone who suffers from mental illness, but I don't think Charles understood the illness well enough to use them.
Early in the marriage, Charles fired a lot of his staff and cut off many friends, but he resented it. Diana tried to fit into his world, but she did things like taking riding lessons and then having an affair with the instructor, so I don't give her much credit for that.
In my opinion, both parties were equally to blame until about 1988, when Diana started leaking to the media and deliberately upstaging him. The marriage was over when Charles realized that he could not trust her to keep his confidence. They couldn't repair the marriage unless the two of them learned to communicate. But you can't have honest communications if one party is blabbing intimate matters to outsiders.
Both of them were having affairs, but Diana decided she wanted more children as Harry and William went off to boarding school. We can discuss her real reasons for wanting more children, but Charles thought it was a bad idea to bring more children into the marriage and I think that is what set Diana off. The rest is, unfortunately, history.