Hi Dillan,
Thanks for reaching out. I understand how frustrating it is to be stuck in a family group after deleting the parent email. This happens because the organizer account controls the group, and without it, the system doesn’t allow members to leave on their own.
The best resolution is to recover the deleted parent account using Microsoft Account Recovery. If recovery isn’t possible, you’ll need to contact Microsoft Support for assistance in removing the group. In some cases, adding another adult account as an organizer can unlock the “Leave family group” option, sign in at account.microsoft.com/family, invite an adult email, accept the invite, then leave the group.
Can you confirm if your account shows as an organizer or a child account? Also, do you have access to any other adult account you can add?
I hope you find this information helpful. Please let me know if you have any further questions If the answer is helpful, please click "Accept Answer".
Regards,
Carlo