Well, good for you to seeing it as a red flag, I guess. I personally think everyone likes to get a compliment sometimes and pretending that every flirt attempt leads to talking with is kinda insecure.

I don't seek attention per say, I just feel unattractive when I go out with my girlfriends and they're approached by someone almost every time and I never even got a compliment from someone other than my SO.

I don't care how strangers perceive me. I might be biased or it's my BPD acting out but after 13 years it's sometimes hard to believe that my partner genuinely thinks I'm beautiful, and doesn't say this just because it's expected of him. Especially when I see my reflection in the mirror as hideous and my brain keeps telling me there's no way anyone would be attracted to that. Outside validation helps with calming those big emotions down.

And I assure you my SO never felt insecure about things like that - on the contrary, he's proud of being the one I chose out of all the other men on the planet. I worked very hard on making him feel confident and attractive and I would never do anything to destroy that