There are many types of relationships out there, when I was younger I had a relationship that was more friendship based and honest in the way that we were very much alike and could speak openly about many subjects, including love and sex with previous partners, just generally like best friends with a sexual relationship, we grew close and made each other laugh but there was something missing.
I could have ended up with that man but the drive and effort needed to make it exclusive for a long time was not there. Eventually I met someone else, good looking, just the type for reproducing, he felt the same and from that point a conditional contract was drawn up, it didn't need to be verbally discussed to death, we both knew each other wanted to be manogamous, emotionally, physically and financially, to work as a team.
I think when you meet that match there has to be that level of trust to bare your soul, your weaknesses, your vunerability, it's frightening stuff and takes some real courage to allow yourself to let go and love one person fully, totally and forgo all others to keep one another safe and secure, but you both want it.
Love has many parts to it and I think, and I don't mean to be rude but if you do not care about infedelity then you have not fully given yourself to someone, you have held back to some degree in certain areas of your relationship.
So as I was saying, do you have children, are you married, do you have a mortgage togther are you tied financially in any way?
Only you know your own unique contract that holds you together but to analogize for your lack of understanding for the pain many feel for affairs could be this..
Imagine your partner coming home tommorow, you have your boundaries, you love him and feel you could never be hurt by his actions as you have a pretty flexible relationship, allowing him greater trust and forgiveness, but if you found him to have a second life, a wife, children a house and you never knew, would you be shocked. He has broken your contract, you only said affairs were acceptable.
As for describing that pain, my analagy for you would be imagine your parents if you love them and they love you, all your life nurturing you, making you feel safe and secure in the world, well imagine turning up at their house tommorow and they shut the door in your face, tell you to fuck off when you ask what's wrong, they say nothing is wrong. Then you find out they have re written their will out to the next door neighbour and left them all their money, and they do not want to see you or your children anymore.
You ask why, and they tell you and everyone in the family you are fucking crazy and will phone the police if you do not stop bothering them.
It's brutal and barbaric.
It's the confusion that hurts, that one day someone loves you and the next they hate you, how on earth you ask could they have ever loved me if they could switch so easily. Have I imagined my whole life up to this point ? It's very scary to wake up with a completely different reality.
Quite frankly you wil be less hurt if you do not give all to love, yet despite all my hurt I don't think I could have gone fifty years not experiencing that exclusive love.