2.4 Infidelity as secrecy and betrayal

A final way that the literature defines infidelity is on the one hand, in terms of secrecy of behaviour and on the other hand, experience of betrayal by the other partner. There is research support for this definition (e.g. Luo et al., 2010; Hertlein and Piercy, 2008; Henline et al., 2007) but defining infidelity in this way moves away from a behavioural operationalisation of the construct; in theory any behaviour that is kept secret or evokes a sense of betrayal can be defined as infidelity.

An even more broad definition of infidelity is also found in the literature, in terms of behaviours which break a couple’s contract, violate couple norms or contravene assumptions about relationship exclusivity (Hertlein et al., 2005; Boekhout et al., 2003; Drigotas et al., 1999). As Hertlein et al. (2005) point out, these broad definitions make it quite likely relationship partners will disagree whether one of them has engaged in infidelity, which underlines the tension between useful breadth of definition and problematic lack of precision.