Every character ghosts you if you turn down their booty offer... It's just how the game is designed
But it doesn´t make any sense that you lose their storyline just because you rejected their romance "in a good way". Moreover, if that´s the case, you shouldn´t be able to do the "trick" to interact with them and add them to you party, plus the exclamation mark on her head...I don´t think it´s working as intended being one one of the big storylines that, in fact, still appears on my mission log.
