I think the horrible and vitriolic nature of the Johnny/Frances Spencer divorce made it out of the ordinary. Diana also claimed to have witnesses her father hitting her mother.
It was just before the 1969 Divorce reform took effect so there was no concept of "no fault" divorce and proceedings were not held in private either. The claimant had to prove "fault" - cruelty, adultery, insanity etc and all the gory details had to be presented in open court.
The same for the custody case - Johnny Spencer sued for full custody by claiming that Frances was an unfit mother. So again everything was heard in open court, with the intention to destroy the credibility of the other party. The evidence played out with the press present. Frances' mother, Lady Fermoy, supported her son in law, the Viscount, and gave evidence against her daughter.
Then as soon as Viscount Spencer gained full custody he shipped them off to boarding school - not unusual - but I think Diana and Charles had been home-schooled prior to this. So it would have been traumatic to have their parents separate, live with their mother in London, a huge scandalous court case, forcible removal from their mother, but rather than going "home" it was off to boarding school and then a few years later Johnny married a woman that Diana couldn't stand.