Are we allowed to invite someone (in this case, my wife) to sit in on confession while confessing? Or is the invitation not mine to give (as in God invited me so it isn’t an option)?
No, you cannot invite someone to “sit in” on your confession unless that person will in some way facilitate the confession (e.g., translate). The sacramental seal of confession is absolute, binding the priest and anyone who facilitates the confession or who listens in on the confession (either deliberately or inadvertently). To ask your wife to listen in on your confession would be to place a terrible burden on her. Not only would she be forbidden to ever reveal anything she heard during the confession – under any circumstances, to the point of martyrdom if necessary – but she would be unable even to discuss it with you later. In any case, no priest should allow this kind of arrangement.
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