People need to read her letter, in full.   
If a person cannot form a full sentence, slurring words, or is unconscious, sex is never "consensual".   Can you go and sign any legal document under the influence?  No.  So the same goes with sex.
It is NOT ok to have sex with an unconscious person.  If you do think it is ok, then you are a sexual predator and the act is called predatory rape.