does my friend not want me around anymore or am i overthinking?

so, i recently decided to put myself out there online hoping to try to make some friends. i clicked almost instantly with this one group of people, especially one of them, who i found out shared one of my favorite bands. i started admiring her, really wanting to get close to her as a friend, and at first she reciprocated and we got on great. then a little under a week ago, she started talking less. i’m noticing she uses all caps when greeting our mutual friends, but not me. i keep getting dry texts and one liners. just now, me and our mutual both said hi to her, but she completely ignored me and started only speaking to our friend. i’m gutted.

it hurts. i desperately want her to like me. she’s older than me (we’re both adults) and i think she’s so cool. i get so excited whenever she talks to me at all, but if i suspect that she’s even slightly pulling back it ruins my day and i feel physically sick. i’m starting to resent her. if the friendship is over, i wish she’d just tell me outright, but she won’t. yesterday i gave in and asked if i was making her uncomfortable and upset, and she said no and told me that i’m sweet and kind. my other friends keep reassuring me too, that she has nothing but good things to say about me, but i don’t believe them. i feel like i did something to make her hate me but i can’t pinpoint what. things were originally going so smoothly.

i’m so afraid of losing her but i also know how deeply she brings down my mood. i just crave her validation, she reminds me of someone i used to know who felt like an older sister to me. i miss having that connection with someone. i have abandonment issues among other mental health related problems, which she’s aware of. i can’t tell if it’s that or if she no longer likes me. please, please help, because it’s tempting to unadd her on everything and disappear.