Firstly, it would be
kinda childish, immature and impractical to measure love in such a
way. Words are cheap - action speaks louder. Let me tell you, when
real situation do take place, everything changes.
The girl's disappointment is because SHE DIDN'T HEAR THE
THINGS SHE WANTED TO HEAR. 
Ok, most guys are blocks of wood when it comes to the 'correct'
answer to return whenever woman post silly and cute questions like
these - She asked hypothetical questions, she received hypothetical
answers.
P.S: Your friend worship idol dramas, love theme movies, shows and
stories?
Cheers