Reflections · Individuals
Internal boundaries: the protection you carry with you
An internal boundary is a filter between other people's behaviour and your inner state. External boundaries control access — what you'll accept, what happens if someone crosses the line. Internal boundaries control absorption — what you let in, what bounces off, and what you set aside to examine later. You need both, but the internal one matters most with narcissistic tendencies, because you can't write house rules for every grandiose moment you'll meet. And you will meet plenty — not because the world is full of narcissists, but because grandiosity is a move most people make some of the time.
Narcissistic tendencies: most people, some of the time
Let's take the pressure off the word. Diagnosable narcissistic personality disorder is relatively uncommon — the large U.S. NESARC epidemiological survey put lifetime prevalence at about 6.2% of adults. Which means the overwhelming majority of narcissistic behaviour you'll encounter this year — the one-upping, the blame-shifting, the taking credit, the inability to say "I was wrong," the contempt that leaks out when someone feels small — will come from people who are not narcissists. It will come from ordinary people being grandiose under stress. Your boss before the board meeting. Your father at dinner. Your spouse mid-argument. You, on a bad enough day. In Relational Life Therapy we'd say people oscillate: when shame threatens, some of us collapse one-down into it — and some of us jump one-up, above reproach, above you. Grandiosity is shame's bodyguard. (If the question underneath is whether you, or they, are actually a narcissist, I've written that up separately.)
That reframe matters practically, because if narcissistic behaviour is weather rather than a rare species, "just cut those people off" stops being a strategy. You can't cut off everyone who occasionally goes one-up. You need protection you can carry into any room. That's the internal boundary.
External vs internal boundaries — and why the external one isn't enough
Most boundary advice covers only the external kind, and external boundaries matter: they define what behaviour you'll participate in and what you'll do if a line is crossed. But they have a limit — they regulate the other person's access to you, not the impact of what already got through. The internal boundary, a concept developed in Pia Mellody's boundary work and central to the Relational Life approach to boundaries I practise, is different. It's a filter that sits between what someone says or does and what you take in as true about yourself.
| External boundary | Internal boundary | |
|---|---|---|
| What it controls | Access and behaviour — what you'll accept, and what you'll do if it continues | Absorption — what you take in as true, and what bounces off |
| Where it lives | Out loud, between you and them | Silently, inside you |
| Requires their cooperation? | Partly — they can push the line and force a consequence | No — it works whether they cooperate or not |
| Works in the moment with a boss, parent, client? | Often not — you can't always walk out or lay down terms | Yes — invisibly, in any room |
A wall keeps everything out — including love, feedback, and connection. Boundarylessness lets everything in — including other people's distortions about who you are. The internal boundary is the adult middle: permeable to truth, sealed to nonsense.
How to build one
1. Buy the half-second. When something sharp lands — the dig, the dismissal, the rewriting of history — the untrained response is instant: it's inside you before you've decided anything. The whole skill starts with a beat of daylight between their words and your interior. Feel your feet, take the breath, and let the sentence land in front of you instead of in you. You're not suppressing; you're queuing it for inspection.
2. Run the filter. Mellody's triage is beautifully simple. Ask: is this true, untrue, or uncertain? If it's true — even 10% true — take that part in, feel what you feel, and use it; an internal boundary is not a defence against feedback. If it's untrue, let it bounce: "that's theirs, not mine," and notice you don't owe a rebuttal. If you're not sure, set it on the shelf and check it later with someone who knows you and will be straight with you. Most people skip the triage entirely — they either swallow everything or deflect everything. Both are boundary failures.
3. Contain your own blast. Internal boundaries run in both directions. The same membrane that filters what comes in should contain what goes out — because the fastest way to lose to grandiosity is to match it. They go one-up, you go one-up, and now it's two people being narcissistic at each other. Holding your own reactivity isn't weakness or surrender; it's the difference between responding and detonating.
4. Give up the argument for reality. This one is hard for capable people, and I say that as a recovering litigator of dinner-table disputes. You do not need the other person to agree that they were dismissive, unfair, or wrong in order for it to be so. Needing their sign-off on reality hands your boundary back to them — it makes your inner state hostage to a concession that someone in a grandiose moment is constitutionally unable to make. State your piece once, cleanly, if it's worth stating. Then let the verdict be yours.
5. Mind the shame gap. Here's the catch: internal boundaries are exactly as strong as your relationship with yourself. If you carry old shame — a standing verdict of not good enough — then every criticism, fair or wild, finds a receptor waiting for it. The filter can't reject a charge that some part of you already believes. That's why this work sometimes has to go deeper than technique, and it's a lot of what I do in individual therapy.
When it's someone you love
If the grandiosity you're filtering belongs to your partner, internal boundaries are the beginning, not the end. They'll keep you steady in the moment — but a marriage where one person routinely goes one-up and the other quietly files it away is a marriage drifting toward distance, and that pattern is precisely what couples work exists to change: both people learning to come down off the one-up, own their side, and repair. And one honest line I won't blur: an occasional grandiose moment is human; a sustained pattern of control, contempt, or fear in a relationship is something else, and it calls for real support, not just better filtering.
The goal of an internal boundary was never to keep people out. It's to be so solidly on your own side that you can afford to let them in.
Common questions
What is an internal boundary?
It's a psychological filter between other people's words and behaviour and your inner state. Where external boundaries control access — what you'll accept and what you'll do if a line is crossed — an internal boundary controls absorption: what you take in as true about yourself, what you let bounce off, and what you set aside to examine later. It works silently, in any room, and doesn't require the other person's cooperation.
What's the difference between a boundary and a wall?
A wall is indiscriminate — it keeps everything out, including love, fair feedback, and connection, and it usually reads as coldness. A boundary is selective: permeable to what's true and nourishing, sealed against distortion and contempt. Walls protect you at the cost of the relationship; boundaries protect you inside it.
How do I deal with a narcissistic boss, parent, or co-parent I can't avoid?
Lead with the internal boundary, because your external options are limited. Buy a half-second before their words land, triage what was said — true, untrue, uncertain — take in only what's true, and give up needing them to admit fault. Keep external boundaries for behaviour that's genuinely unacceptable, and keep them about actions, not their character.
Is everyone a little narcissistic?
Narcissistic traits exist on a spectrum, and most people show some — especially under stress or shame, when going one-up feels safer than feeling small. Diagnosable narcissistic personality disorder is far less common (a large U.S. epidemiological survey estimated about 6% lifetime prevalence), so most of the grandiose behaviour you meet comes from ordinary people on a bad day, including, occasionally, you and me.
Why does criticism stick to me even when I know it's unfair?
Usually because it lands on old shame. If part of you already carries a verdict of 'not good enough,' unfair criticism finds a receptor waiting for it and the filter can't reject a charge you partly believe. Strengthening internal boundaries then isn't just technique — it means healing the shame underneath, which is deep, doable work.
Do internal boundaries mean I just tolerate bad behaviour?
No. Internal boundaries protect your inner state; external boundaries still handle behaviour. You can be unabsorbing and clear at the same time: let the contempt bounce off internally while saying, once and plainly, what you will and won't participate in. The internal boundary just means you're no longer negotiating from inside the wound.
What if it's my partner — should we get help?
If one-up moments are frequent enough that you're building defences against your own partner, that's exactly what couples therapy is for: both people learning to come down, own their side, and repair. And if what's happening is a sustained pattern of control, contempt, or fear rather than occasional grandiosity, that's beyond a communication problem — please reach out for real support.
A note: This article is general information, not therapy or a substitute for it. If you're in crisis or need urgent help, please call or text 9-8-8 (Suicide Crisis Helpline) or call 9-1-1.