Thank you.
Not only did he cheat on Diana. He married her purely because it was expected to have a appropriate wife. He never meant to be faithful, never loved her, never even tried to be a husband. He did his duty to father some heirs, used her as a brood mare, and then continued to break her heart and spirit, bit by bit. He is a spineless troll.
They used her and abused her. Chewed her up and spit her out. She was such a good person, so young. When she finally found the strength to break away and find a bit of happiness for herself, they destroyed that too. How very alone she must have felt.
There is nothing fairy tale about that family and never has been. One only has to look into their history, which goes a long way back and is interesting if nothing else.
I do wish Diana's sons well. They are the legacy she left behind and there is a lot of her in them still, or so I hope, for their sake.