The most damaging workplace relationship: the frenemy
There’s something uniquely exhausting about the person who’s nice one day and cutting the next.
The frenemy dynamic
I once had a boss that I thought I admired.
He was full of praise one day, but then brutally telling me off the next for seemingly minor errors (and sometimes in front of others). People used to tell me “he’s only like this because he cares about your development”. I convinced myself this was the case.
It wasn’t until I left that workplace that I realised how unhealthy the dynamic really was. I never knew what version of him I was going to get.
This is the frenemy dynamic. It is a workplace relationship defined by emotional unpredictability. One that toggles between support and sabotage, praise and passive-aggression. It can manifest itself in situations with bosses (like mine) who can’t decide whether they’re your mentor or your critic or peers who are nice to your face but then undercut you privately.
This piece explores that dynamic and why it’s so damaging. I’ll also share a few ways to manage it, in case you ever find yourself stuck in a frenemy relationship.
Frenemies are the most dangerous people at work
When we think of toxic workplace relationships, we tend to picture the obvious culprits: the micromanager, the bully, the manipulative colleague and the like. But the people who often do the most psychological damage are far more subtle and, counterintuitively, not always the awful ones. In fact, they’re sometimes wonderful, which is the very problem.
The most dangerous person in the office is the person who’s emotionally inconsistent. Their behaviour swings between supportive and undermining. That kind of relationship is what psychologists call ambivalent or, in plain terms, a “frenemy.” It’s a connection that mixes warmth with hostility.
In his writing, Adam Grant describes this as the “Dr. Jekyll and Mr. Hyde” effect. And further research backs it up: people in ambivalent work relationships experience more stress and worse health outcomes than people who work with consistently negative colleagues. This is because you never know what’s coming next.
This toxic pattern can manifest in both peers and managers
Contrary to popular belief, the ‘frenemy’ dynamic isn’t confined to peers who you may be competing with. It can also show up in colleagues who are more senior or more junior.
With peers, it is often colleagues are supportive to you in person but underhand you in other ways. For example, you think you’re working together but then they take you off emails. Or, they’ll take credit for a project even though they were simply covering you while you went on leave. They’re friendly when it serves them, but distant or dismissive when it doesn’t.
With managers, the impact runs deeper because they control your progression. Their ambivalence can show up through inconsistent feedback or blurred boundaries, like taking a special interest in your development, then using that to guilt you into doing things that serve their goals, not yours. Over time, you may find yourself managing their moods more than your actual workload.
What makes these relationships so destabilising is that they’re hard to walk away from. Unlike someone who’s consistently hostile, frenemies keep you hooked with occasional kindness. That keeps you emotionally invested long after you should have stepped back.
Ambivalence is more damaging than outright hostility
Research consistently shows that inconsistent behaviour is more stressful than consistent negativity.
This is because your nervous system doesn’t know what to prepare for. When someone is reliably difficult, you can build armour and figure out how to manage them. But when someone’s behaviour is unpredictable, your brain is constantly on high alert, ready to pick up the next shift in tone or treatment.
It was summed perfectly by Adam Grant in NY Times opinion piece on the topic: “it’s unnerving to hope for a hug while bracing yourself for a brawl”.
Needless to say, this unpredictability is bad for your health. It can lead to:
Increased anxiety and overthinking as you (naturally) replay conversations in your head, unsure what to make of them
Higher physiological stress as studies link ambivalent ties to elevated heart rates and blood pressure
Diminished trust as you stop feeling safe around such individuals, even when things are going well
These findings were backed up by a study on police officers which showed that those with ambivalent work partners reported worse outcomes i.e. more stress, more health complaints and even more absenteeism than those with openly hostile ones. This finding applies to workplaces, where the emotional toll of having to deal with frenemies affects job performance and commitment, motivation levels and reduces productivity of workers.
You need to spot the frenemy dynamic before it wears you down
In dealing with ambivalent relationships in the workplace, the first step is identifying them. This is more difficult than it sounds because the relationships don’t necessarily look toxic and it is easy to second guess oneself (or tell yourself that you are overreacting).
So, in diagnosing whether a person is a frenemy, you need to spot the pattern. Do this, by asking the following questions:
Do I feel anxious before meetings with this person, unsure how they’ll act?
Do I leave interactions feeling confused, drained or on edge, even when they seemed fine?
Do I replay conversations in my head, trying to make sense of their tone or motives?
Do I sometimes admire them, but also deeply mistrust them?
If you’re vacillating between appreciation and discomfort, chances are you’re dealing with a frenemy.
Dealing with the frenemy
Once you’ve identified the frenemy relationship, the goal is to reduce the frenemy’s power over you. That doesn’t always mean a direct confrontation, especially if the person is more senior or politically well-connected. But it does mean being vigilant about how much access they have to your time, energy and emotional bandwidth.
That can look like:
Adjusting your exposure: Limit one-on-one time where possible. If meetings are unavoidable, try to include a neutral third party or keep communication in writing.
Strengthening your support systems: Invest in relationships with colleagues you trust. Decompress with a mentor, speak openly with a friend outside the team or seek informal guidance from someone senior who understands the politics.
Create a paper trail: Follow up verbal discussions with a written summary (“Emailing to recap our discussion earlier — I’ll move forward with X by Friday”). This builds a paper trail and reduces ambiguity.
The point isn’t to fix the relationship as much as to fortify yourself. The more grounded and supported you are, the less impact their unpredictability will have over your self-confidence.
Wrapping up
It’s always worth pausing to consider whether emotional unpredictability might be showing up in your own work (or personal) life and what it’s costing you.
One of the hardest parts of a frenemy dynamic is that it rarely feels bad enough to justify walking away. You’ll have moments of connection, which is what makes it so corrosive. But inconsistency is its own kind of harm. Over a sustained period of time, this can adversely affect your self-trust, stability and focus, leaving you depleted.
Don’t ever forget: someone doesn’t have to be constantly toxic to be damaging. Sometimes, inconsistency is enough.
I can definitely recall a particular manager who was a frenemy character. Luckily I didn't trust her from the moment I met her so i had her at arms length straight away. I did witness others who suffered from the unpredictability of her, even her own boss.
I think you've given great advice on how to deal with a Frenemy!
Such a well-written and approachable article, especially for a complex topic. Growing up in the world of M&A, I always thought of dyads (group of two) in terms of mathematics. Most relationships aim for 1+1=2. Anything less than 2 isn't worth the energy. But the real question became, how can we make 1+1=3... or more! This is huge piece of that puzzle, whether is people or firms, we should always aim higher!