Deal with fiancee's resentment before tying knot

Q. I've known for a while that my parents are not my fiancee's favorite people, and didn't totally understand why until my fiancee recently revealed she's still simmering over a comment my dad made over a year ago that my mom eagerly "me-too"-ed.

It was a dumb and petty comment about someone else's appearance that my fiancee took as a subtle reference to her.

My parents don't have that subtlety. If they wanted to critique my fiancee, then they would, and they haven't.

My fiancee is now saying, "Hey, that's just the way your folks are, it's obvious what they must think of me, and that's fine. I'll just interact with them less."

My parents are none the wiser about her simmering anger. But it's manifesting itself as her wanting to have them less involved in our lives, which is not what I want.

Anything I can do to nudge this toward a happier future, or do I butt out and let things run a natural course?

A. Here's the "natural course" of someone who takes an innocent if dumb remark about someone else, escalates it into an imagined personal slight, uses the manufactured offense to stoke a long-running secret fury, and then cites that fury in a barely veiled threat to stand between the source of the remark and his grown child: to poison countless other relationships with her petty and poorly managed anger.

So I vote no on the run-its-course thing.

No no no.

Your fiancee's actions over the past year-and-a-half have spelled out for you the following:

She has very thin skin.

She does not speak up when she is upset.

She piles up secret resentment.

She does not face this resentment like an adult, instead striking the disingenuous tone of an adolescent.

She thinks it's OK to stand between you and your parents because she is upset - without giving them or you any chance to explain yourselves or make amends.

Please, please see how unhealthy this is. Your fiancee is showing signs of profound immaturity, insecurity and poor self-esteem, which are the unholy trinity behind so many abusive and controlling relationships.

Already she is several pages into the "Isolate From Family" chapter of the abuser's playbook; you admit plainly that you want to keep seeing your parents, but you're just as plainly willing to "butt out," as in, not resist her plan to keep you away.

This isn't just about your parents, either. If she thinks it's OK to use react-resent-reject tactics on your parents, she'll do it with whoever she perceives as a threat - your buddy from college, your neighbor, the couples you hang out with, and eventually? You. Or worse, your someday kids.

When you stand up to her on this, expect her to threaten to break the engagement. Let her. Such threats present a false choice between standing up for what you think is right - keeping an open mind till your parents can explain themselves, say - and being with her. It's a false choice because to a healthy couple, integrity itself is not an existential threat.

So trust this, and challenge her. Full disclosure, I don't see emotional wellness in her future anytime soon, and therefore not in yours if you stay with her. Think about it: using a year-and-a-half-long silent grudge on a perceived slight to distance you from your parents. Wow. And she doesn't even see yet how unwell she is.

But you don't either. Assuming you're not ready to leave, at least stand up for what's right. "You've made my parents pay for months without allowing them to defend themselves. I won't accept that." Hold firm. It's not siding against her or siding with your parents - it's taking maturity's side. Find out for yourself whether she's able to join you there.

Q. I wonder about the general principle of using another person as a reason to address or change things in your life - especially things you can't seem to change for yourself. In some scenarios, I can see this as wonderful: A parent stops drinking for his kids, a spouse modifies bad eating habits for their spouse, a parent (in your column) faced a fear of social interactions for her kid.

I see that "I lost weight for you" or "I tried [whatever] for you" might be unhealthy in some situations.

There are changes I would dearly love to make. However, I don't feel like I alone am deserving of these positive gains - but it's a no-brainer for me to effect change for someone else.

So, without cornering you into giving a reductive, binary answer, can I ask your thoughts?

A. I think you're conflating a change made for someone else's benefit with a change made for someone else's approval.

The latter puts your success in someone else's hands, and is therefore unhealthy - but the former is about seeing someone else as a reason to become the person you want to be. That success is measured only by you.

• Email Carolyn at tellme@washpost.com, or chat with her online at 11 a.m. each Friday at www.washingtonpost.com.