But the story doesn't seem that strange, she developed a romantic attraction to him over time with out any pressure of dating or sex. It not like an unattractive guy she didn't know approached her for a date and she forced herself to go out with him while being physically repulsed just in the hope that he had a great personality.
Guy that was not ugly, but not her type, stuck around for multiple months/years, treating her well, with no pressure, only indicated his interest once, none of the men that hit her checklist were approaching, she started genuinely become friends with dude and that transfered into romantic feelings. Sounds cool.