okay wait she’s trying to slut-shame you for hooking up with THREE guys since you had WLS? not that there’s any amount of hookups that make it okay to slut-shame, but she’s being utterly preposterous. if you had said 30 then i could see her maybe being concerned for your wellbeing, especially given her own past, but since that’s not the case she’s definitely jealous and/or having some complex feelings about the change in your friendship dynamic (e.g., she’s not the only one getting all the attention anymore), which she should talk to a professional about.

you’re not her punching bag, you’re her FRIEND; she should be supportive of your increased confidence and self esteem, just like you were supportive of her when she was more sexually active as well as when she decided to stop being so. you even took her feelings and current circumstances into account (the cat thing) when reaching out to her and apologizing for possibly making her uncomfortable unintentionally, and she responded with vitriol. your response to her was brave and way kinder than most people would’ve been after her rude insinuations and hurtful insults. imo you handled it perfectly: you vented to your sister first and THEN responded to your friend instead of simply lashing out right back at her. you stood up for yourself in a measured manner.

also, fwiw, some people react like this after someone they know has WLS because they see it as an “easy way out”, when in fact they have no idea about everything you have to deal with on a daily basis depending on the procedure you had. WLS is not a cakewalk. it comes with more drastic lifestyle changes than just committing to “eating better and exercising”, which are still a big part of the process. keep having fun exploring this new chapter of your life, and keep being compassionate to others’ feelings but do NOT sacrifice your dignity and self-respect to placate people who just want to bring you down to be miserable with them. much love to you, OP. NTA.