I can only imagine what a blow it is for someone off serving only to find out their partner/spouse, girl or boyfriend has betrayed that kind of a trust.
I wish people, all, could just be honest with themselves and with each other before they jump in together too far. People change, design and build their lives around accommodating a certain kind of relationship, they structure their lives to fit that "particular kind" of relationship in ... doing and deciding things they would not do if the relationship were different. Whats wrong with that is it goes farther than a simple betrayal of monogamy, its a life betrayal to the person who has changed their lives and built life and daily decisions around to accommodate it, and thats why people get tied in knots and griefstricken when they're doing "monogamous whether stated or understood to be monogamous" and find out their partner has strayed. It's not so much about being with someone else, its about highhandedly disrespect towards that other persons life and freedom to choose how they want to do their own lives and relationships. Kinda like ripping off the other persons life and running the relationship and their life. How come? "I want you ... and I want so and so too but know you won;t be with me if I am open about that and I really gotta have you so I'll have my cake (you) and secretly eat it too (others)"
I would make different life and relationship behaviors choices for a monogamous relationship than I would for one with someone who wants other people too. In the end, all I really want is to know what I'm doing with my own life, day to day, and that I'm not crossing my own lines and can make decisions I know I can live with as long as I am with this person.
I think sacrificing what you really want for another person is not a good foundation to try build a relationship on, or hold onto someone you don't want to lose. I think a lot of grief ... and maybe a lot of bitter separations and divorces come out of "sacrificing"
All depends on what people want with and from each other. Know what you want, and what you want from other people, and try hanging in there for the person that fits.
I know "love" and instant attractions hit and people dive in hungry to have and hang on ... way too far and too soon ... blinded by love and lust
;D ... then ......... oh boy, hang on for a bumpy ride.
These are just some of my thoughts about relationships and cheating etc. Most of us learn the hard way not to jump too far too soon
How does that person handle situations and life ... good things to learn before diving in only to drown or be hurt. I'm old and have been hurt by my own "too far too soon" problems, inluding not so long ago. Slow learner I guess