Deleted iCloud Photos staying in recently deleted folder

Approximately 3 months ago, I deleted a number of photos n a shared album with my ex. The folder was ‘unshared’, the album deleted, and the photos inside it deleted too. All my photos are shared across my devices though iCloud.

Recently, I have become aware that it’s likely she’s somehow maintained access to these albums and folders, and potentially accessing other photos of mine due to comments she’s made that she would only know if she’d seen photos.

Earlier today, I went into my recently deleted photos and found that the photos deleted 3 months ago are sitting with ‘29 days’ remaining before they are permanently deleted, when I haven’t viewed or restored them since deleting! Is this evidence that she somehow still has access to my photos and those images/album?

And regardless of the above, how do I check what access someone has to my phone and iCloud shared documents etc, and how do I remove that access permanently? Because as it is, I cannot see anywhere that she could still be connected.