Hax: Give sister-in-law the benefit of doubt

Dear Carolyn: Last summer, my sister-in-law cheated on my brother. It was a months-long affair that continued even after my brother found out about it, and was followed by some other odd/out-of-character behavior that led my brother, and eventually her, to suspect mental health issues.

Although it seemed like they were headed for a divorce, my sister-in-law rather abruptly agreed to start attending therapy and working through their issues.

They are expecting a baby this summer. The timing (apparently the pregnancy was planned) suggests that they conceived essentially the moment they decided to stay together … which concerns me. The rest of my family, none of whom knows about the affair, is over the moon with the news.

My brother understands where I'm coming from, but it's still awkward when we talk. Any advice? I want to share in his joy, but I'm horrified that a baby seems to be how they decided to patch up their marriage (as far as I know, they've stopped going to counseling).

And I want to forgive my sister-in-law, but my hatred for her is still very real and very fervent.

Perhaps most urgently, I am finding it increasingly difficult to not "out" my sister-in-law every time someone says something glowing about her. If I did that, I would really ruin the close relationship I had with my brother.

Carolyn says: It also really wouldn't help your brother — and when the whole reason you're upset is that someone made his life gratuitously harder, you don't want to be the next person to make his life gratuitously harder.

There is a time and place for skepticism like yours: When you're the one deciding whether to marry/reconcile/procreate with someone, or you've been asked to advise the person who is.

But here the decisions have been made, and your counsel is not being sought. Now it's time to make your sister-in-law the beneficiary of any doubt.

You have a lot to work with: "It seemed like they were headed for a divorce"; "apparently the pregnancy was planned"; "the timing suggests"; "a baby seems to be how"; "as far as I know."

You know a lot less than you think. You know she cheated, they reconciled, they conceived. Beyond that, zip. So embrace that, make it work for your brother, if not for you.

Start by forgiving her, since humans do stupid stuff; since you do stupid stuff, too, and presumably want second chances; since this stupid stuff is bad but not unforgivable, right?; because the chief beneficiary of any forgiveness, this included, is the forgiver herself.

Affair? Maybe it was the byproduct of poor mental health, which is now being addressed.

Baby as marital glue? Terrible idea, yes — but maybe it wasn't an idea. Maybe the pregnancy was unintended. Maybe it galvanized them. Maybe they'll beat the odds.

Counseling? Maybe they still go.

You don't need any of this to be true, or even likely — you just need possible, enough to invest you in your brother's success. Where there's no positive spin, file it under acceptance of human frailty.

It'll take time, yes. But even if the marriage implodes, it's time I doubt you'll regret having spent.