Oculus and Facebook accounts can be linked but remain separate accounts.
When I created my Oculus account, I logged in and created the account through Facebook. I later ended up deleting the Facebook account, which unknowingly also deleted my Oculus account. I ended up losing all games that were on that account. I was told that I needed to unlink the two accounts before deleting Facebook, or the oculus account would be deleted also. That should not be the case. Facebook should only be used to access the account, not share in deletion.