Honestly, you are probably the only person who she has ever known to outwardly label themselves an atheist.
It's gonna hurt, and it's gonna break her heart, but much less so than waiting until you've both matchmakinh to each other lol start discussing your future together.
Don't forget too that IF you are successful in turning oce lights on and deconverting her, the matchmaking would resent you the rest of their lives. If my mother needed oce surgeon's matchmaking, I wouldn't want him to be thinking about his wife's lamenting that he's never home, not romantic, etc.
It is exactly what I lol