Not at all, we've wrestled with these feelings for a long time and sometimes its hard not to feel ashamed or guilty or even used, but in the end it all comes down to trust and respect, for each other in the relationship and from and for the bull.
We've come to see that there are tons of other people out there who enjoy this lifestyle and for us we've come to realize that it's not wrong, it might not be the same as everyone else out there but this is who we are and we're happy with it, the world is filled with many different types and people should just be honest with who they really are.
I struggle with the same questions and feelings. NO you're not a worse person because you have these feelings. If you can work this out as couple and all parties feel good about what's the problem ? Everyone in the triangle of course must be honest. I fully agree with the previous comment.
As far as married couples go, it all depends on how each individual spouse feels. If both feel it is exciting and adds excitement to the marital relationship, absolutely not, and its really no one else's business.
As far as developing "trust" in a marriage, IF the male part was to desire having occasional sexual affairs with other females, would the female spouse agree to his doing that? What I've found is ... in most cases NO. Married women struggle with this 'cuckold' desire of men anyways; it makes no sense to many of them as to why their spouses would want them having sex with other men. So, have they really developed a trusting relationship, often not.
My wife doesn't have an issue with me having sex with other females as long as its in her presence. She would never allow me to go out on dates or have an overnight affair. Its not that she doesn't trust me; she says she doesn't trust other females.(hoooohummmm)