I am not using superstrong strong passwords for affiliate accounts, that is overkill imo. I use different login names though, bunch of emails and of course proprietary email(s).
I would be much more concerned about the attack vector, you can use as strong passwords as you want but if attackers have access to your device or email, it is pointless. Old password does not mean and should not mean that your acct is hackable.
Are you sure the old password is the reason of the hack? Why?
If you talk to God, you are praying; If God talks to you, you have schizophrenia.