A Taboo
This was a huge event that still hangs over the royal family to this day. It is part of the reason they do not approve of divorce even more than the typical person does. Many believe that it was the reason the Queen did not show up for the religious part of the wedding between Charles and Camilla in 2005.

A Taboo
Not To Offend
There is a very good chance that the Queen wanted to go and see her eldest child get married for the second time. However, there were rumors that said that she did not want to seem like she was prioritizing him over what the Church of England believes in. Even though divorce and remarriage are no longer forbidden, it still advises everyone not to do these things.

Not To Offend