Hi there allround, I tried to have one of these relationships with another person before I met my husband and it just didn't work.
A relationship for me is just that, monogamy is important, I married my husband because I love him and want to spend the rest of my life with him, it may not be perfect but it's still owrthwhile, its invaluable actually.
Is it possible your friends husband is wanting perfection without the reality of what life truly is??
Life isn't meant to be perfect if it was it would be completely borring and uninteresting. Sex is important in a relationship but I think maybe some people get get caught up in what I call the
begining feeling - gushy excited newness of a relationship. once they get caught up in this they try to constantly emulate it by creating new relationships. They don't seem to have the ability to learn about true aspects of relationships which really are 80% hard work, 20% of its naturally easy.
I got hurt and so did my partner at the time and it ended up tearing us apart because at the end of the day if he wanted to spend intimate time with another women then he should just go and be with her, not have me sit and wait until he felt like he wanted to be with me because she was getting real. Its raw and to be honest extremely selfish thing to do to someone.
I could continue but will let our wiser and older friends have a go at this one.