I think you answered your own question OP.
How long have you been looking for your perfect cardigan?
And you found it. And it's not cheap. Perfect things are never cheap.
And then the question is, what does this perfect thing mean to me?
How valuable is it? Why do I want it? What will it bring to my life/wardrobe?
And ignore the 'precious' posts, there's absolutely no point owning something so desired and then not using it.
Moths? I've had moth problems, moths love dark and dusty corners,
Keep your wardrobes clean, keep all your corners clean!
If you do have moths parasitic wasps are the best for long-term solutions. Three cycles and they are done for. Top up once a year.
Washing? Take no notice of the madness around cashmere, I put £1k pieces in the washing machine in a delicates bag, 20 or 30° with a wool wash.
Depending on weight I either hang to dry or press and then hang.
There's absolutely no point owning something that you're too scared to wear because of care of cost.
It's entirely possible to own expensive clothing, and wear it as everyday. There-in lies the joy.
Don't deify, it's just clothes, no matter how beautiful and precious, they have utility, use them, love them, that's why they exist.