AITA. Wanting my boyfriend to remove his tattoo

Long story short he was with his ex for over 10 years. She ended up cheating on him along with other issues. He has her name tattooed on him. The tattoo never really used to bother me too much but now it’s just a constant reminder of the what ifs and if he still loves her even if it’s so deep down he doesn’t realize it. They do have kids together and seem to co parent pretty okay. Everytime we’re in the same room though they tend to argue or she picks on him in a flirtatious way or she asks him for his advice and guidance with things. It seems like she still has feelings for him. When I bring up the tattoo he seems to get defensive “you want me to get rid of something I’ve had for 10+ years”. I don’t know why he wants that constant reminder of someone who obliterated his heart, and why he feels I should be okay with this tattoo. It makes me feel like I’m just the place filler for the person who never loved him as much as he loved her. I love him with all of my heart. He is the best partner I could’ve ever asked for. I know everyone has a past but does this past truly need to rub itself in my face everytime I’m with him? Am I being unreasonable in this ask?