accept

proposal / suggestion

to propose / to suggest

deception

trompe l'oeil

stem or continuative form of だます (damasu) [godan]

he / distal demonstrative, something far off removed from both speaker and listener: that / boyfriend

distal demonstrative, something far off removed from both speaker and listener: that, yon / particularly, male personal third person pronoun: he / by extension from he: boyfriend

he; boyfriend

(と〜) thinking that […] (with the next clause explaining that the truth is contrary to expectations)