We don't know that it was 'from time to time', we have no idea what the parenting situation was from the time of her parents divorce ...
But, whatever the arrangement... and however bizarre and abusive the hot spoon is viewed now, in 2022 .. it is something that some of us experienced and it wasn't done with malicious intent nor was it damaging or scaring to most. Myself included.
Many of things are done, by parents or adults to children or each other, purely because it was done to them and until someone says 'hmmm I don't think this is a good idea, let's not do that any more' ... midwives used to hold a newborn by its feet and slap it's bottom at birth for example... we don't do that now but it once was accepted as common practice.