Is this animal abuse?

Well i don't think you need to ask , I am sure you know yourself this is not good for the poor animals, in NZ if you denie a suffering animal treatment,(and believe me if it not suffering yet, it will be eventually) as like with cancer you can be prosecuted and it has been done here, so check out your laws on this and if that is the case let her know so,now on the other hand maybe you could offer to help her raise the funds for the much needed treatment to ease this ferrets suffering, have a garage sale or something, whether she has the money to spend on clothes,makeup etc still does not alter the fact that an animal is going to suffer, so my approach would be first check out the laws in your state, and tell her so, and then to offer to help raise the funds.