Those who are fans of the popular 1970s sitcom All in the Family and its various spinoffs know that Archie and Edith Bunkers daughter, Gloria, was married to Michael Meathead Stivic, who was constantly at odds with his blue-collar, bigoted father-in-law.

In later seasons, Gloria and Michael have serious relationship issues. Gloria has an affair with a fellow faculty member of Michael, who was teaching at the University of California, Santa Barbara. Subsequently, Michael abandons Gloria and their son Joey, for one of his young UCSB students.

Bad, bad, enough.

Imagine, however, if the scriptwriters had chosen, instead, to have Michael engage in an extra-marital affair with Archies 18-year-old niece, Billie the daughter of Archies brother Fred.

Then, like the real-life storyline of many adulterous men and women, it really could be said that the infidelity that took place was all in the family.

Believe me, when it occurs in real life, all-in-the-family infidelity is no sitcom, and it doesnt resolve itself by next weeks episode.

As messy as infidelity is when it takes places during business travel or with a co-worker or neighbor, its vastly more difficult to survive and recover from when the person your partner cheats with is an in-law, member of your extended family, or a close friend.

Opportunity Knocking

I know of no credible statistics that report how often such affairs take place. But they are not as rare as you might imagine.

Infidelity grows out of opportunity. That exposure can be very limited for example, a glance of two strangers across a restaurant bar but often it arises from repeated contacts, over weeks, months, even years.

So, really, its no surprise that husbands do sleep with sisters-in-law, wives sleep with brothers-in-law, and cousins, nieces, nephews, and other relatives find themselves physically and emotionally drawn to extended family members.

Infidelity is a body blow whenever it arises. Now imagine how it feels to discover that your husband not only cheated on you, but he did so with your first cousin. (Or your wife with your uncle.)

Even when its a best friend, rather than a blood relative or in-law, the circumstance is the emotional equivalent of getting run over by a car that then backs up and runs over you a second time while youre still knocked flat on the pavement.

Throw into the traumatic mix the impact that all-in-the-family infidelity has on children, grandparents, other siblings, and other close family and friends, and even wise King Solomon would be challenged to disentangle and set right what two individuals momentarily blinded to any need but their own wreak.

Im certainly no King Solomon, but I do have some suggestions directed at couples who are hoping to get through all-in-the-family infidelity and work toward constructing a stronger, more fulfilling, lasting relationship.

Where to Start Rebuilding

Surprisingly, just as human nature gives rise to some individuals who cheat on their partners with family members despite all the many good reasons to avoid such a situation so, too, does human nature offer pathways none easy for couples to rebuild their infidelity-shattered lives, together.

For starters, its crucial to be familiar with each of my 7 Infidelity Survival Steps, which Ive outlined in previous articles here on Psych Central:

  1. Cease All Contact with the Outside Person
  2. Prove That the Affair Has Ended
  3. The Partner Who Strayed Must Feel Genuine Remorse for His or Her Betrayal
  4. The Partner Who Strayed Must Accept 100% of the Responsibility for His or Her Actions
  5. Make Time to Discuss the Affair and Your Feelings
  6. Work on Having a Normal Relationship
  7. Building a Health and Happy Relationship

The first, and most obvious special challenge that arises when the infidelity is all-in-the-family is that its much harder, if not impossible, for a cheater to cease all contact with his or her lover, since the romantic partner is a member of the extended family.

When your spouse or committed partner cheats on you with a sibling or other close family member and you elect to remain together and try to work through your relationship ills you must be realistic about whats in store.

Remaining together will often be unpleasant, awkward, and require a willingness to come face-to-face with your partners lover at family functions for years to come likely the rest of your life without stewing over the affair and feeling hurt and bitterness at each encounter.

If you understand this clearly, and have the ability to genuinely put the past behind you, it will increase the odds that you can reconcile and rebuild your relationship. If not, you would be wiser to make a clean break and not allow yourself to be a perpetual victims of your partners betrayal.

[Note: When you are divorced, its likely that you will still show up at family events where your ex-partner and his or her lover are also in attendance. The difference is, if you are divorced, you and your ex generally will have lower expectations of one another. Moreover, even if each time you see your ex and his or her lover you feel a surge of anger and renewed sense of betrayal, at least you wont have to live with it daily, and it will serve as a reminder of why it is that you got divorced.]

A Steeper Climb

If you are the partner who strayed with a family member and now, recognizing your error, are committed to doing whatever it takes to restore your committed relationship, you face an even steeper climb than a cheater who strayed with a non-family member.

Lets call the partner who strayed John, and the partner who was betrayed, Sue. [The genders could be reversed and my advice would be no different.]

John must let Sue have total say when it comes to how theyll handle family events when Johns ex-lover will be in attendance. Sue is the injured party and John is in debt to her.

If Sue asks John to stand by her the entire time, eliminating any potential one-on-one time with his ex-lover, then thats what John should do. If Sue asks John simply not to attend future family events, he should also abide her wishes.

[I recommend you read my Psych Central article, When Infidelity Is an Uninvited Guest at Your Thanksgiving Dinner, for some tips on how to handle family events in the aftermath of infidelity.]

In some cases, all-in-the-family infidelity incorporates an additional element an expression of strong anger that manifests itself as cheating behavior.

If John betrays Sue by sleeping with Sues sister, Carole, it may be Johns immature (even subconscious) way of getting back at Sue for some perceived wrong. After all, if John has an affair with Carole, its a double betrayal of Sue his and Caroles. To inflict so much hurt on Sue, John must be operating with an element of anger or some sense of being justified in his actions.

And why does Carole betray her sister, Sue? Is it also out of anger?

Not necessarily. Life is complicated and Caroles motivations for sleeping with her sisters husband may simply come down to being lonely and drunk. There are no easy answers or explanations.

I generally recommend that couples who are trying to survive infidelity seek help from a marriage or relationship counselor. Doing so increases their chances of success.

Likewise, when close family members are caught in the swells of infidelity such as Sue and Carole they may independently require the intervention of a therapist to help them repair the damage that the infidelity has brought to their relationship.

All-in-the-family infidelity is only a subset of the much larger universe of relationship infidelity. It is, however, a particularly virulent variety of betrayal and one that, unfortunately, is not uncommon.

Reading Resource

A strong marriage/partnership is the best defense against infidelity. I recommend you download a copy of my e-book, The 8 Marriage Rules for a Passionate Marriage, from Amazon. It costs only a few dollars, but is rich in practical, proven advice. I advise readers to invest about 8-minutes a day, for about three weeks. The benefits of doing so will last a lifetime.