Pay Pal is a bit safer than most but as a general rule, I change passwords on that even though the person I'm paying doesn't get my password in their system.
However, that being said, if you had to create an account with her on her website and you used the same password on her site that you have anywhere else (email, YT login, etc) then you should change it.
General rule of thumb is to never ever use the same password for your banking or financial sites that you use anywhere else and your email password should be unique as well.
Forums and junk sites you are on you can create generic password because it really doesn't matter to hackers to gain access to the site. If they find your password for a junk site like forums or game sites then they will try to access your email account with the same password.
Once again, passwords should be unique on your email, banks and financial stuff.
Your email password should be super duper secure. Keep in mind, once someone hacks your email they can just look through your emails, request new passwords from any site they see in your mailbox and take over your life.
Be safe!
