[...]
Let's do 3 steps if you want noone to access your account in future.
- Change your account email to a random email.
- Change your account password to a random and very strong password, can not crack.
- Log out your account. You will lose it forever and noone can log in it.
Wait --there is one more important before OP will vanish his account.
-Delete all your posts that can be found on your post history.