How can I stop my friend without hurting her feelings?
	
	
		Hi, I'm a female and I'm 21 years old now. I have a dear friend, let's say her name is A. A is a sweet kind of girl and we've been friends since we're 9 or so. When we're in high school, she dated this boy named B, a friend in the same class of her. 
I thought they are a good match until 3 months ago A called me while crying because she got dumped. I know B is a good person, so I asked him personally why he dumped my friend. B said that he feels that she had never loved him from the start and weirdly, she constantly talks about me even on their dates. B also said that she's somewhat a freak and I should be wary of her. 
The next day I visited her apartment with the spare key, only finding her gripping a knife near her chest. I freaked out and tried to comfort her but to my surprise she confessed her feelings to me. I couldn't speak a word that time finding that my friend is actually a les**an. She ra*ed me, but after that she apologized. I couldn't say anything but nodded that time, and it was maybe my biggest mistake. 
After that ra*ing incident, she constantly confesses to me. A is now quite forceful,though I never said yes to her confessions. She used her broken heart as a shield and reason to kiss or violate me. She actually even used ropes and binding just to have what she wanted. I wanted her to stop, but I don't know how. I see her like a thin glass and I'm afraid I will hurt her, knowing she neither have parents alive, nor any relatives nearby. What should I do and say?