An email address can only be used with one account. Once the account has been deleted you will be able to add the email address to your current account. Probably best to wait a few days after the deletion before trying to add it to the current account. read more
Changing your email is normally not a big deal, but when it comes to Facebook, it's a bit more complicated because your email address is also your Facebook login mail ID. You can change your login mail ID on Facebook by navigating to the Facebook settings page and confirming your new email address. read more
What you would want to do is add a new email address and after you get the confirmation email to that address and click the link in it to confirm it, go to your Settings again and make the new address your Primary email address, then you can remove the old address. read more