A "No Refunds" policy is both offputting and pointless. EBay gives sellers a little boost if we allow returns within 14 days or more.
And of course, if you take Paypal, you do take returns.
Tell your customer to return the item for a full refund. She should for her own protection use a Confirmed Delivery service. Since this will cost her $20 or more from the USA to Canada (if you were both in the USA it would cost less than a quarter), she may be unwilling to do this. You could accept photos of the broken items instead of the actual items themselves.
The idea is that neither buyer nor seller should have both the item and the money.
From your point of view, the DC is not necessary. It would only be useful if the buyer goes for a Paypal dispute. PP will only refund if the buyer can prove the seller has received the item.
The buyer did make one mistake. She threatened you with negative feedback. After the transaction has been satisfactorily concluded, you have the item (or proof that the item is damaged beyond the price paid for it) and the buyer has her payment back, if she does leave negative feedback anyway, you can have it removed because of that threat.
Every seller gets Unpaids. I've got one open right now. In my opinion, the best outcome with an Unpaid is that the buyer never pays and the item goes back on sale. Your experience is why.
BTW, put your buyer on your Blocked Bidder List. Use your Seller Preferences to Block automatically bidders with UID Strikes. You can also Block bidders who do not have active Paypal accounts. These are all useful protections.
