Ah, I see now--you're using Elements for online Backup/Sync. If you want to continue to keep your images backed up online, they must reside in albums in Elements which are enabled for sync in Elements preferences.
If you want photos/albums to be backed up online, you don't necessarily have to share them. As the account owner, you'll see all the albums listed in My Gallery when viewing your account online. Guests visiting your gallery will only see albums you've set up for Share, and not the same list of all albums you see (the ones you've backed up via Elements).