Infidelity
Summary: Not always linked to personality disorders, cognitive bias, emotional immaturity or deception. But look a little closer, and statements and justification may offer more insight into why someone would lack the respect many have to fix, process or develop pathways with consideration.
Corner cutting can cut deep; knowing the aftermath and the bizarre behaviour, it's a reason many won’t risk a legal commitment called marriage with emotionally immature or hidden baggage to ensure the situation is turned upside down with an unreliable self, self-centred, impulsive situation where children suffer for decades.
Two types of lying: Withholding and falsifying. Knowing a reality or an agenda and purposefully withholding while working a facade. Cheaters may find reasons to justify and blameshift. Seek professional advice to avoid gaslighting.
Speaking from a long-term soul mate position, not being judgmental, being witness to a number of situations that just shock if one were to walk in those shoes. Spot the signs early. Connection and sharing time should be the priority, quality time.
References:
VeryWellMind: Infidelity: Signs, Types, and How to Cope
NIH - Love and Infidelity: Causes and Consequences