Try to stay if you can, just make a new account for now. What makes you think that someone has access to your account? Did you come to the site address & get automatically logged in? That will happen if you dont clear the cookies (history is good to clear as well of course).
End of the day, you getting help for your drinking isn't a news flash that many would be interested in (sorry to say ;-). It is however very important to us.
Take care & keep coming back... even if its under a new name or 10.
NB