she says i’m her best friend, but i’m not so sure

for context she (and sorry if this is the wrong sub for this) is my manager. i've known her for about six months and we got along pretty well. at the beginning i was always cracking jokes with my direct manager at the time and her, and making sassy comments which she really liked. fast forward a few months we're just hanging out and she suggests let's be best buds. alright fine with me it's always good to be on the good side of a boss. however i've noticed as time goes on we don't really hang out or do anything "best friendie" besides her calling me bestie and pookie, and inviting me up to the conference room to catch once in a blue moon. we've never hung out outside of work, i besides just being in the same area of the museum for a few minutes we don't spend time with each other like she does other co-workers. i always see her passing by with her other friends who seem to be around her more than i. she says hi but that's about it. i realize she's a manager and has more responsibility, but if we are "best friends" it doesn't really seem like it. she and i both share and interest in running and she said she really wants to go to one of my races, but that's not for another month. maybe i am just jealous idk.