Exes🙄

Okay, so I need advice from any girl out there who has problems with their gf/bf's ex. My boyfriend doesn't understand how much it bothers me for him to reply to her birthday wishes every single year and for her to text him randomly to start conversation. I know they have dated awhile but for some reason she keeps creeping up and it makes me annoyed knowing he'll always respond to her. My boyfriend refuses to block her on social media and ignore her texts which is the worst part.. Am I wrong for feeling this way?