My husband doesn't seem to be attracted to other women...

I know, it's a weird one! I shouldn't really complain about it, but my husband seems to have a complete lack of interest in other women. I don't just mean staring at the odd bum walking down the street, I mean actresses and models alike!
He even seems to not really get excited by me sometimes, don't get me wrong, our sex life is great! But multiple times I've told him I'm going to go to a sex shop with a girlfriend and did he want me to get an outfit or prop or sexy lingerie he just seems really turned off by the idea?!
​I'm probably being stupid, but it does upset me sometimes. I've told him, the only reason I offer to get stuff or do things is because I want to turn him on and I want to look good for him, and he just isn't interested!
Am I overreacting? Any thoughts?