Q. I’m writing on behalf of a friend I’ll call “Claire.’’ For the past year, she’s shared details of an evolving relationship with “Brian.’’ At first, it was about navigating the early stages of a relationship — different communication styles, habits, accommodating schedules, defining the relationship, etc.

Gradually, it’s shifted toward something I’m uncomfortable hearing. A few months in, Brian sent Claire a series of dark messages related to her relationship history. They’d discussed past partners, in broad strokes, at his request. Claire hasn’t dated a lot. But from that conversation, Brian seemed to make a number of bizarre judgments about her behavior and character, and in his e-mails accused her of sleeping around, lying, and misleading him. Claire took a step back, but eventually decided to give him another chance. Brian apologized, said he would work to change, etc. However, it doesn’t sound like that’s happening. One day Claire will gush about something thoughtful Brian has done, and the next she’ll mention that he has accused her of cheating; showed up to her house to give her the silent treatment; rewritten a previous encounter (blatant gaslighting); or inserted chaos whenever he doesn’t feel like the center of attention.

Throughout this, I’ve tried to walk the line between letting her know when Brian’s behavior isn’t OK, while still supporting her decisions. I don’t want to put her in the position of needing to choose between her boyfriend and her friend. At the same time, I also don’t want to make her feel bad for giving him additional chances. She loves him and hasn’t given up on his ability to change. I don’t know how to be a good friend to her through this. Is it enough to reinforce her reality — to help her trust in her own memory, and her qualities and strengths? Am I doing her a disservice by holding back on harsher criticisms of a bad guy? Are there other ways to help her without overstepping?

A concerned friend

A. People will say this isn’t a love letter, and I suppose it isn’t, but this is a “support people through love’’ letter, and I think we should discuss it. It’s a challenge to advise a friend who needs relationship help when you just want to tell the person to leave their partner. It sounds like Claire wants you to share her optimism . . . but you don’t have to fake it.

My advice for giving advice is to ask all of the right questions. “How does that make you feel?’’ “Is his behavior improving?’’ “What kind of partner do you want in the future?’’ Sometimes talking about these things — out loud to a friend — helps with clarity.

Also know that you can share concerns about the relationship without stating them as a list of criticisms. As in, “I’m worried about how much you’re doubting yourself.’’ That’s more productive than “Brian is the worst.’’

Know that when it comes to abusive behavior, you can — and should — be honest. Validate her memory and all of her strengths, but also let her know that what she’s describing isn’t healthy.

It does sound like you’re doing a good job, by the way. If you doubt yourself, you can always ask the most basic and important question: “How can I help?’’

Meredith

READERS RESPOND:

Tell her that men come in “as-is’’ condition. ST-AUGUSTINE

I was the listener for a friend who’d been in a toxic relationship for years. I heard about the same issues over and over and over again and nothing ever changed. Finally I told her I just couldn’t be the person she talked to about it anymore. I don’t know if my reaction had anything to do with it but she ended the relationship soon after. It’s one thing to be a friend, but at a certain point listening becomes enabling. PHATALISTIC

This reminds me of the “Sex and the City’’ episode when Carrie breaks up with Big for the millionth time. HAPPYDAZED

I would have given different advice in my twenties than I am now giving in my fifties, now that my filter has faded and I’m not so worried about what people think. ASH

Ah, the lack of a filter and aging. That’s what is happening to me. WHOOPIE!!! MHOUSTON1

Column and comments are edited and reprinted from boston.com/loveletters. Send letters to meredith.goldstein@globe.com.