Over the past many years, we have learned so much about what feeds chronic infidelity (and often keeps it change-resistant) from disciplines and modalities besides psychology and addictionology, though psychology has certainly been instrumental to our understanding. Still, it's not the only frame to consider, by any means.
What has interested us the most here has been adding the vectors of sociology and feminism in our quest to understand the context that infidelity behaviors occur in.
After all, behaviors don't happen in a vacuum, nor are family of origin issues and earlier traumas the only variables that impact the development and trajectory of repetitive behaviors once they form. By repetitive behaviors, we refer to the lies and manipulation tactics Betraying Partners use as much as the infidelity behaviors themselves as each reinforces the other.