Some time ago I read a blog that noted that while the idea of open relationship has some acceptance in the general community, the suggestion of open marriage is met with horror. The very idea that someone would be married AND sexually active with other people is, even among younger people, generally seen as sacrilege. Then the writer went on to say there are many reasons people have open marriages but didn’t elaborate.
I have no doubt that what the blogger said about most people thinking that for a couple to agree to that one or both are free to have extra marital sex is somehow fundamentally opposed to what marriage should be. It just so happens that particular day I introduced a doc student to the word Polyamory. Her immediate response was “Oh, it’s like having a mistress”. My experience from both talking to people and reading is that most monogamists think that open marriages are simply about the man bedding every skirt he can catch. However, my first-hand experience says that is not so.
My wife and I have been poly for twenty of our thirty years of marriage, so it is not a “fling” for us, it is how we live our life. Though we came to an open marriage after we were married, we do have friends who got married explicitly stating that they were not to be monogamous. At a wedding we had a groom tell my wife it was fine with him if the bride and she continued being sexual. I’ve been the wedding photographer for two weddings where there was group sex after the reception. So, non-monogamy is not just when a couple take a fling either.
The first thing both my wife and I tell people who ask about open marriage is this simple fact: Having an open marriage does not mean we are having sex with other people, it means we can if we choose to. It’s the fact the door is always open that makes our marriage open not that we go through it. Some years we've had a lot of extra-marital sex, but some years we have little or none. The truth is neither of us have been on a "date" in well over a year, but we still have an open marriage.
An overview of marriage research over the years, including DNA studies of family groups, will show that lifelong monogamy is very rare indeed. One DNA study showed it is not the norm even in women who claim they are monogamous. So one fairly can say it is not having extramarital sex that makes for open marriage, but when the partners agree extramarital sex is always a positive option. I said we have had an open marriage for twenty years, but in reality we have had an open marriage for several years longer that because I explicitly gave her my OK to take a lover several years before she actually had sex outside our marriage for the first time.
Couples have open marriages for a variety of reasons, in our case we had waited to have sex with each other until we got married and then found out that we had a significant difference in our need for sex. She expected sex twice a day every day once we were married. Due to some biological limitations I was more prepared for twice a week. This caused strain and led me after five years to let her know that I was fine with her taking a lover. That circumstance is not at all unusual.
To this day some men look at me like I’m crazy when they find out my wife dates on her own (and has sex) but I generally have not over the years. But throughout our 30‘s & 40’s had a much higher social and sexual need than I did; and, by dating and having lovers she got that need met. I have never seen that as a threat to my manhood, nor am I afraid the love she develops for others will reduce the love she has for me. Now we are older, it is more egalitarian and I have been with people without her in the last five years. I put forth our example that as evidence it is a misconception that open marriage is about the man having permission to have a mistress.
While it is true that does happen. No one we know well has this type of arrangement. Men who want a mistress just have one, that’s not an open marriage. Some open marriages afford one or both spouses to have sex with people of their own sex. Other open marriages are about the sheer excitement of the chase, both individually and as a team. Poly type open marriages are about expanding ones circle of close intimate friends and sex is just a by-product of that. And one type that is particular common with older couples is that the husband is no longer capable of vigorous sex and they bring in younger men to act as the husband’s surrogate, often holding and kissing his wife while another man fucks her in his stead.
Among our friends, there as many reasons to move beyond monogamy as there are individual marriages. The “Love American Style” model of wife swapping as the norm may well have been true in 1970, but you can be sure it is not so today.
I write all this to suggest there is no one "best" reason to have an open marriage and there is not "best way" to work it out. What I can say that any move away from monogamy must be preceded with a great deal of talk and mutual agreement; and then the couple must proceed in a way that works best for both of them.