What do you think about me being mad at my wife's ex buying her bras?
Do you think your wife and her ex are still getting together?
No, but him buying her things pisses me off. My wife's ex is a jerk who only cares about his own selfish needs.
Having your wife's ex buy her things like bras is a reason to be upset, but launching your criticism at him and calling him names is not a correct response. Confront your wife and her ex about this behaviour without the attacks.
I asked him to stop, but he won't listen to me.
You handled the situation responsibly. You should talk with your wife and tell her that this makes you uncomfortable.