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Advice – My BIL cheated. How can I support my sister?

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/u/WoodWizzy87 on /r/relationship_advice writes…

“BiL [31M] has been having emotional affair the last 3 months and turned physical the last month or so and he brought the woman back to their house every time. Sister [30F] has moved her stuff out of their house, had to go get std test, and they have started counseling. It sounds like he fell into the trap of attention from someone else and couldn’t stop. Hundreds of decisions where he could’ve said no and he couldn’t. My [31M] sister says she wants to try and work this out because she believes he’s still in love with her. I tend to be more cynical and protective and believe it’s the sunk cost fallacy and he may love her, but isn’t in love with her.

If she tries to make this work and he regains her trust that may work. I will support her decisions since that’s the “moral thing to do”, but how do I ever regain trust with somebody that literally ripped my sisters soul and heart out and just stomped all over it because of selfishness? I don’t even want to see the guy ever again.”

Dear Wood Wizzy 87,

There are two different issues at hand here. The first is in regards to the relationship you want to maintain with your sister. The second is in regard to the relationship you do not want to maintain with your brother-in-law. Before we talk about each of your relationships, let’s first talk about infidelity.

Your relationship with infidelity.

In her TED Talk, Esther Perel reframes infidelity as an act that is “universally forbidden, yet universally practiced.” According to this 2005 study from Blow & Hartnett, 25% of committed couples experience infidelity throughout the course of their relationships. That is per relationship. Considering that we have multiple partners throughout our lifetime (and some with multiple relationships at the same time), great majority of us have either personally dealt with infidelitous relationships or helped our loved ones deal with their infelicitous relationships. I also suspect that this figure could be a lot higher now that we define infidelities in all different ways. So it really does appear to be universally practiced. Now let’s think about why it is so universally forbidden.

In that TED Talk linked above, Esther Perel goes into more depth about why infidelity is so universally reviled. She hypothesizes that much of our aversion to infidelitous relationship is due to how much more important and focused on relationships have gotten in just the past couple decades alone. Cheating has become this greatest act of betrayal, a mistake in which we stake our entire identity upon. How many of us are marked forever as an Adulterer following one or two mistakes in a relationship? Our monogamous sanctity has become the crucible in which our best ideal selves reside, detached from realities of the every day life. Cheating has long preceded our monogamous agreements. So why are we so fixated on how wrong infidelity is?

Try your best to remove yourself from the societal conditioning on what makes infidelity feel so inherently bad. Outside of this situation with your sister and your BIL, consider why you are feeling so bad about his transgressions. Why does it personally affect you so?

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Your relationship with your sister.

I really feel for your sister. She is clearly going through a lot in her own relationship, and is using her familial support to keep herself rooted and standing straight when the weight of her world feels heavy on her shoulder.

You had an interesting dichotomy at the end where you recognized that your sister wants to keep trying with her husband, while you remained cynical. Have you considered where that cynicism stems from? Do you think it could be because you aren’t in love with your BIL the same way your sister is?

That feeling of protectiveness you feel toward your sister, your sister can look out for that on her own. She too is an adult, capable of handling her own relationships.

You were also able to recognize that you want to support her. Do so. And continue to do so. Support in this form is altruistic and nonjudgmental. Be there for her. Talk her through what she has been experiencing. And try your best to not hold onto the pain she has been venting onto you. It is your responsibility to support your sister through this. She has decided that she wants to continue patching through and work on this relationship with her husband. So be supportive of that in whatever ways you think it means. That leads me to my next point.

Your relationship with your BIL.

You absolutely do not need to see your BIL if you do not want to. After experiencing second-hand what your sister has been experiencing, that would be an absolutely fair boundary to establish for yourself. If you need to make yourself scarce in these holiday times, do so for yourself. Your anger is justifiable in both logical and emotional sense. Your BIL did inflict some pretty intense pain on your sister and your family at large.

But he too is your family. Not one that you chose, but one your sister has chosen for herself and her family. And he too is human. We all make mistakes. If your sister decides a major part of recovering her relationship with her husband involves him recovering his relationship with her family at large, that also includes you. So embrace the pain and hurt you feel, but ultimately learn to let those feelings go and learn to forgive your BIL. He may not have yet earned your forgiveness, but allow him the space to do so. He owes you and your family a level of emotional debt, and he too should be allowed to reclaim and reforge his connections as well.

Good luck.

Tea Time with Tomato is an informative relationship and sex advice column for both monogamous and polyamorous folks. By submitting your post, you agree to let me use your story in part or in full. You also agree to let me edit or elaborate for clarity.

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