I don't know how old you are, but I get the feeling you're pretty young still, and when you are young, shit changes alot, especially feelings. I doubt that the ketamine or any other drug would snap her out of being in love. I think it has more to do with the fickle nature of young women (and men), and the problems that she is not dealing with by constantly stuffing chemicals into her pie hole.
Love is never more intense than when you're young, too, so I know how you feel. The tragedy is, it's also never more fleeting. In fact, if I were to venture a guess, I would say that love, and how we handled it, is the main reason most old timers like myself wish we had it to do over again. It's a gift and a curse, young love.
Hang in there.
The Rev