How you treat people on your bad side tells a lot about your character

Q. My girlfriend and I recently moved in together to counteract our busy schedules, and it's good. There are adjustments, and we're getting to know each other better.

I don't know what to make of her relationship with her dad. He keeps reaching out to her, inviting us to dinner, forgiving her loans, etc.

She stays in sporadic contact, but is cold and distant. She is very tight with divorced Mom.

I wasn't there when she grew up (no abuse) and can't judge, but my parents and I are close.

Is this a character flaw that after 10-plus years she still can't forgive him? What if I get on her bad side?

Missouri Guy

A. Oh, Missouri Guy. I don't like "shouldas" I try to offer different perspectives, not back seat driving but this one is so glaring I feel I have to say something.

One of the most important things to know about someone, if not the most, before you make a home together is how she handles people who get on her bad side. It's just a clear, concise, extremely reliable measure of character.

Does she turn on people lightly, arbitrarily, or only on matters of substance and only when they present her with no other choice?

Does she stoop to silent treatments, duplicity, gossip, revenge and other emotional war crimes, or is she forthright and civil in choosing to keep her distance?

Does she close herself off permanently once crossed, or is she open to forgiveness based on the relative severity of the harm done to her and/or on the sincerity of efforts to make amends?

Since you've already commingled your stuff, you'll have to figure this out while pretty well invested. Not ideal, but better now than kicking it down the ever-more-committed road.

So explore the subject by learning the answer to another key question (also better asked pre-commingling, but …): Can you talk to each other about difficult things without one or both of you getting defensive?

You're asking a really good question about your girlfriend, her family history and her current emotional makeup. Please pose it to her directly, in a dukes-down, non-accusatory way: "I notice your dad is trying hard, and that you're not buying in. What's the history there?"

If she doesn't think you're close enough to ask that, then, predictably, all I can say is that she moved in prematurely with you.

Q. Recently, my stepson and his new live-in girlfriend have been having verbal and physical altercations. They both came to us for urgent help in resolving the situation. We advised that it would be best if they discontinue living together, and then decide if/how they want to proceed. They have since disregarded our advice because "they are good now."

My stepson has a birthday coming up. My husband wants to have a formal dinner for him and, presumably, the girlfriend. I'm not sure I can play along like everything's fine. And, frankly, I'd rather not attend at all. Both of these scenarios are going to cause me marital strife. What do I do?

Lose-Lose

A. Lose-lose for you, maybe, but mightn't this couple benefit from having family close? And observing how healthier pairs interact? And turning to you in emergencies? I'm sympathetic to you, but please do go for them.

• Email Carolyn at tellmewashpost.com, follow her on Facebook at www.facebook.com/carolyn.hax or chat with her online at noon Eastern time each Friday at www.washingtonpost.com.

© 2014 The Washington Post