Hazumu loved Yasuna long, long before she realized Yasuna couldn't see men. She wanted to be there to help her, yes, but that wasn't pity.
Breaking them up was horribly, horribly out of character and poorly written. Yasuna just passes it off with an "I'm horrible, aren't I?" and Hazumu, Hazumu who was *heartbroken* after the original rejection and felt like utter ass when she seemed to have been caught betraying Yasuna? Just seemed to pass it off like it was nothing? Yeah, QUALITY writing there.