Fiancée Demands An “Open Relationship” Just Months Before International Destination Wedding

Wedding planning is inherently stressful, but for the original poster (OP), the pressure reached a boiling point over a fundamental disagreement on the meaning of marriage.

Already working through the emotional baggage of his fiancée’s past emotional affair, the OP noticed her becoming distant and disinterested in intimacy as their November destination wedding approached.

When he finally demanded answers, the explanation blew his world apart: inspired by her friend group and an online blog, his fiancée wanted to transition their relationship into an “open” one.

The proposal, which included the idea of having one-night stands on nights out, left the OP physically ill. When his fiancée begged him to consider a polyamorous lifestyle, he walked out to get some headspace at a friend’s house.

Now, sitting with his thoughts, the OP is facing the stark reality of calling off both the wedding and the four-year relationship.

Scroll down to see if the internet thinks he should throw in the towel or if there is any room for compromise when a monogamous partner is asked to open up the relationship!

Man considers calling off his wedding after his fiancée proposed opening their relationship

The revelation that a partner wants to alter the fundamental structure of a relationship right before a wedding is a staggering emotional blow.

A universal emotional truth in this scenario is that a request for non-monogamy is rarely a sudden philosophical shift; it is often a symptom of existing relational fractures.

When a partner proposes an open relationship after a history of infidelity, they are often attempting to legitimize behavior they previously had to hide. In this story, the conflict centers on the clash between commitment and novelty.

The timeline OP provides is critical: the fiancée had an emotional affair just before the engagement, and her behavior shifted drastically in October, the exact moment her friends introduced the concept of an open relationship.

From a psychological perspective, the fiancée is experiencing a severe boundary erosion influenced by her social circle. Her subsequent withdrawal from physical intimacy wasn’t just “wedding stress”; it was an emotional detachment from the monogamous contract.

When a partner uses an online blog about polyamory to justify a desire for one-night stands, they are experiencing cognitive dissonance, trying to convince themselves and OP that a desire for variety is a progressive relationship lifestyle rather than a breach of their original vows.

The fresh perspective here is that the fiancée is attempting to secure financial and emotional stability while retaining complete sexual freedom.

By stating she doesn’t have “second thoughts about the marriage, but the nature of the relationship,” she wants the protection of a husband and a family wedding abroad, but without the restriction of fidelity.

To OP, this feels like an illness because it directly invalidates the sacrifice he made when he “manned up” and forgave her past emotional affair.

The fiancée’s plea to “give it a chance” suggests she does not view monogamy as an absolute requirement for marriage, whereas for OP, it is the entire foundation.

Relationship experts and marriage counselors frequently warn against entering an open relationship to save a partnership, a phenomenon known as “Polyamory Under Duress.”

This occurs when one partner agrees to non-monogamy simply out of fear of losing the relationship altogether. When an open relationship is proposed as a fix for distance or past infidelity, it almost always accelerates the breakdown of the bond.

For non-monogamy to work, the baseline relationship must possess an ironclad foundation of trust. Introducing multiple partners into a relationship that is already rocky from an affair is like adding a second story to a house with a cracked foundation.

Furthermore, psychologists specializing in social contagion note that friend groups often normalize toxic behaviors. If the fiancée’s friends are actively promoting a lifestyle of casual flings while keeping their partners as financial anchors, the fiancée is living in an echo chamber that devalues OP’s boundaries.

This expert insight frames OP’s instinct to walk away as a healthy, self-protective boundary. He is not being old-fashioned; he is standing by a core value.

The fiancée’s behavior since October suggests she has been mentally trying on this new lifestyle at the expense of OP’s emotional well-being.

Her desperate begging that “nothing is set in stone” is a panic response to realizing her gamble backfired and she might lose the stable future OP provides.

Since OP is currently gaining headspace at his mate’s house, the most realistic path forward involves a decisive evaluation of compatibility.

An open relationship cannot be compromised on; there is no middle ground between sleeping with other people and remaining monogamous.

When OP communicates with her next, it should not be a debate about the merits of open marriages, but a clear statement of reality.

OP can frame his boundary clearly by stating that he forgave the emotional affair because he believed they were building a faithful life together, but her request to sleep with other men proves they want two entirely different futures.

He can state firmly that he is not interested in an open relationship and will not marry someone who views fidelity as optional.

Calling off a November wedding now is incredibly painful and logistically difficult, but it is vastly cheaper and less traumatic than untangling a marriage that begins with a fundamental lack of respect.

OP’s paws are shaking because his gut knows the truth: the woman he proposed to is no longer aligned with the life he wants to lead

These are the responses from Reddit users:

A dominant theory among users is that fiancée has already crossed physical or emotional boundaries

These users point out the cold, hard logistics of the request

This group argues that fiancée wants the best of both worlds

Commenters pull no punches here, warning you against falling into the trap of “hope.”

This story is a devastating collision between “Relationship Re-negotiation” and “Monogamous Boundaries,” made all the more toxic by a lingering history of betrayal.

On one side, we have a fiancée who seems to be treating her impending marriage like a soft-launch for a lifestyle shift.

Influenced by her friend group and online blogs, she’s trying to sell the concept of an “open relationship” as a progressive upgrade, completely blind to the fact that her timing, right after a previous emotional affair, makes her request look less like “enlightenment” and more like a license to cheat legally.

On the other side, the OP is dealing with the crushing weight of the “Devaluation Pivot.” Having already swallowed his pride to move past her previous infidelity and propose, this new demand feels like a complete breach of the contract he signed up for.

By presenting him with a blog post about live-in boyfriends instead of focusing on their upcoming wedding, she didn’t just cross a line, she effectively demolished the foundation of trust he was still trying to rebuild.

For the OP, walking out wasn’t just about getting headspace; it was a survival reflex against a future that looked entirely unrecognizable.

Do you think the OP’s decision to consider calling off the wedding is fair given the historical stakes of her infidelity, or did he overplay his hand by walking out before the discussion was fully finished?

How would you juggle being a partner’s keeper when their definition of commitment completely warps into something else? Share your hot takes below!