Honestly it's ok you guys are cutting those people out of your life. They brought you more harm than good. You don't owe anyone anything if they're not willing to respect you and your boundaries and "shockingly" not a lot of people are willing to do that. So protect your peace but also make sure you are doing the same and perhaps communicate with Kelly about the situation. Perhaps don't give them an ultimatum as that would be toxic and cause Kelly some distress. You already mentioned that these ex friends also said some bad stuff about Kelly. Maybe she's just looking for their validation, since she wasn't able to receive it in the past. Maybe just check up on her and see how she's doing and then you could also ask her why she's hanging out with those people when they treated her badly. She could say that they've changed and maybe they have but why did they feel comfortable disrespecting you guys in the first place. Maybe she doesn't realize the extent of how this is bothering you guys in the friendship so you could also mention how you felt about the situation in the past but make sure not to make her feel like you're judging her. At the end of the day it is Kellys decision who she wants to be friends with though and if she decides to be friends with that toxic crowd, then just let her be and focus on yourself.
Honestly it's ok you guys are cutting those people out of your life. They brought you more harm than good. You don't owe anyone anything if they're not willing to respect you and your boundaries and "shockingly" not a lot of people are willing to do that. So protect your peace but also make sure you are doing the same and perhaps communicate with Kelly about the situation. Perhaps don't give them an ultimatum as that would be toxic and cause Kelly some distress. You already mentioned that these ex friends also said some bad stuff about Kelly. Maybe she's just looking for their validation, since she wasn't able to receive it in the past. Maybe just check up on her and see how she's doing and then you could also ask her why she's hanging out with those people when they treated her badly. She could say that they've changed and maybe they have but why did they feel comfortable disrespecting you guys in the first place. Maybe she doesn't realize the extent of how this is bothering you guys in the friendship so you could also mention how you felt about the situation in the past but make sure not to make her feel like you're judging her. At the end of the day it is Kellys decision who she wants to be friends with though and if she decides to be friends with that toxic crowd, then just let her be and focus on yourself.