I’m not really sure how to remedy this, but I’m feeling put off that my bf forgot his ex gf’s name!

For context; he was showing me pics from an old Instagram account and came across a few pics of an ex. He tells me they dated for like 3 months. The pics were cute, he was calling her “someone special” and whatnot. It was only 6 years ago and I asked oh what was her name? And he straight up forgot!! Like legit could not remember and he strained for a good couple minutes until he finally remembered. It just makes me feel so gross about him that he would forget a person he dated like that. I get if it was a hookup or one night stand but how the hell do you forget a whole damn girlfriend. Like do people mean nothing to you?

My question is has this ever happened to anyone else? What kind of person could forget someone they had an intimate relationship with? It makes me wonder about how much he values relationships and people. He blamed it on adhd, but I know lots of adhd people and they don’t forget shit like that! What should I say to him?

TLdr; my boyfriend forgot an old ex’s name and it’s making me feel icky that he’s the kind of person that doesn’t value people or relationships at all. Why is this bothering me so much and how should I discuss this with him?