Over reacting or not??

So my half brother I don't talk to him bc he's old af and steals money out of my parents buisness my bf has been friends with him ever since they met and it bugs the fuck out of me when he talks to him bc i dont talk to him bc he talks shit about my parents and has talked shit about me he's 35 and lives with my parents should I be mad bc my bf talks to them or an i over reacting?