You have my sympathy. Sounds like my brothers. Everything is disposable, easily replaced, especially when someone else is footing the bill.
Carelessness and destructiveness aren't just a nuisance, it is a waste of money and resources. Make the case to your bf that holding the kids responsible and teaching them to value and take care of things is an act of love; it will help the kids in the long run. Teach the kids basic economics: if you have to waste money fixing and replacing everything, there is less money left over for other things they want.
