A-Tan obviously loves Hayate, but I'm really thinking that Hayate now loves A-Tan as an old friend of childhood rather than true love. Besides,
They were like what? 5years old when they kissed each other played horseback riding. XD They clearly slept SEVERAL times together in the bed. I know this is animeworld, but I still can't imagine 5year old Hayate and A-Tan having sex.
Or if they didn't yet, why didn't they? LOL xD