Wth. Ugh

My ex sent me a text message saying "off to *city name* for drinks and bitches" I know he purposely sent it to me but he said it was meant for his buddy. After he said something about how he's happy to find someone better and then sent a ;) and I told him that he wishes. He's been really mad lately because he has a DUI and stuff but I still don't get it. Why does he keep texting me. And saying stuff like that ^