Fidellity & the hareem
There is a simple biological problem, there are many people we meet who we could be a partner to. Life and circumstance link us to someone with a level of intimacy that makes us one with another individual. Like all relationships they can go up and down.
The sad reality is there are other partners and needs that we could meet and get involved with, and many who given a choice would jump ship. It is never a thing of comparisons but circumstance and giving in to temptation.
Many do not see the pain, the damage they do to their partner by this bad behaviour. It is like killing someone, taking the most vulnerable part of them and ripping it up. I have read testimony after testimony men who regret the pain they caused and did not realise it, and would never have got involved to that degree if they had known.
The most difficult thing is to realise everyone is unique and deserves love, and is not valued more or less because of the attributes or abilities they have. You do not love your children because of what they can do, but because they are your children. A wife or husband is equally valuable, just as your children are, and moreso, because you chose to share with them and share the most valuable parts of your life.
What is hard is when someone betrays the trust and love, and how this hurts. But Jesus was equally betrayed, and he knew of the damage that does to the soul of the betrayer, because it is they that loose the intimacy and love that was freely given but is now withdrawn.
It is hard though to define yourself as a whole, when such a thing is ripped from you, but that is the reality, but it does not devalue you or your love, in fact it devalues the respect and love the other party failed to have.
But think on this. Did Jesus become less because we are sinners, or did his example show us His love and forgiveness, his very soul conquers and goes beyond our understanding of need, pain, loss, betrayal, into the love God is in His nature.
I can never say how you should react to a betrayal by a partner, but I do know it is Jesus and His love that defines life and healing, and how that changes you, will show you what you need to do next.