I always have to remember that passage, do not remember who the author was, that goes (heavily paraphrased)

Someone: Life would be so much better if that thing happened
Sometwo: yeah except for the coyotes eating our faces off
1: The what
2: Can't just pretend your life would only be good if you changed something in your past. You'd do other things different. You'd get hurt in different ways. You have to take the good with the bad.

I want to say terry pratchett wrote it about Sam and Sybil Vines but I can't remember for sure.
@Mareepy that's Granny Weatherwax and Mustrum Ridcully and Granny mentions "the fire." i believe it's from Lords and Ladies. gimme a bit and i'll grab the quote.
@Mareepy “What about the fire?’ she said. ‘What fire?’ ‘Swept through our house just after we were married. Killed us both.’ ‘What fire? I don’t know anything about any fire?’ Granny turned around. ‘Of course not! It didn’t happen. But the point is, it might have happened. You can’t say “if this didn’t happen then that would have happened” because you don’t know everything that might have happened.
@Mareepy You might think something’d be good, but for all you know it could have turned out horrible. You can’t say “If only I’d …” because you could be wishing for anything. The point is, you’ll never know. You’ve gone past. So there’s no use thinking about it. So I don’t.”
@PsyChuan THANK you it was driving me nuts.
@Mareepy i read a discworld book i'd say once a month so i have probably got most points seared into my brain by now.