You may feel that way, and that's totally fine. Not everyone does, and that's totally fine too. A relationship is whatever you and your partner(s choose to define it as. She's not saying you have to have an open relationship, she's just throwing it out there as ideas people might consider. I think a lot of people don't consider it a viable option, but some people do. That doesn't mean their relationship isn't valid, just different. Something you consider fine might be a huge NO to someone else.