>>7773217 (OP)
My sketchbooks are all just scribbles and studies, so it wouldn't effect me much at all personally, though it is nice to flip through and see my progress.
However if you were the type to do be elaborate finished drawings in your sketchbooks, I can imagine it being akin to all your art files becoming corrupted.
I don't upload any of my art anywhere besides here, so I'd be miffed, because all my effort and time would be gone like piss in the wind.
But the results of those accumulated efforts, my skills remain, so it wouldn't break me, but the disappointment would be immense.
As for your scenario, assuming it wasn't an accident, it'd be an immediate breakup situation; why throw out something so important to your spouse? It seems like some sick power move that's akin to partner abuse (destruction of property), or equally as bad, they are so ignorant your hobbies and passions that they just didn't know (or more appropriate to say; they just didn't care).