Saying youd sell it to them then not doing so is rude and she should be angry, a better way to handle it would be to say if its still available then you can pick it up and if she really wants it she can send you a deposit to hold.
Facebook Marketplace: How To Handle Difficult Buyers/Sellers.
Saying youd sell it to them then not doing so is rude and she should be angry, a better way to handle it would be...