Agreed - open communication is important for such a big purchase, yet at the same time, it's her money owed to her. Did she need permission from him? No - it's her money.... with which she is allowed to do as she pleases.. Sure, perhaps communicating about it to him would have avoided any surprise and upset on his part, but to treat it like a "capital offense" and in a nasty manner? That is not called for and any kind of nastiness is unacceptable. He could have communicated his upset in a respectful manner, as it should be in a healthy relationship. This man, however, is abusive and toxic and did this in an unacceptable and nasty manner, so much so that she lost all enthusiasm for the truck. That personally makes me most angry on the OP's behalf.