I read somewhere about “FIDO” – if you have a problem, rather than brooding on it and wishing you could change the past, Forget It and Drive On.

And I like this, but I think it’s incomplete.
We can’t change it, but the one thing we can do with the past is learn from it, so I’d like to suggest the slightly less catchy “LFIFIDO”:

THAT’s a healthy attitude to problems
Onwards and upwards
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