even if one says

entirely; all

everything, all

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

a counterfeit, forgery / an imitation, replica / counterfeit, forged / fake, false

falsehood, lie / fake, forgery

a falsehood, lie / (logic) a false statement (usually based without facts)

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