Your instance owner can easily change your password and log in as you.
You can counter that by using multiple accounts from different instances. Use at least 3, if one is compromised, you have the other 2 to counter any impersonation attempts. Make sure you link your other instance profiles in every profile description page. Then use an archive website to save each profile page. If any 1 account is compromised, use the other 2 to tell people the account has been taken over by someone else. And you have the archived profile page that links to the alt accounts to verify that it is indeed your 2 alts.