The Science of Boundaries
Why They’re So Hard to Set (and How Therapy Helps)
Many of us know we should set boundaries - with partners, family, friends, colleagues - but when it comes to actually saying “no”, guilt, fear, or discomfort often creeps in. If you’re ever wondered why setting boundaries feels so hard, you’re not alone. Boundaries are more than personal preferences; they’re rooted in psychology, attachment, and even nervous system regulation.
In this article, we’ll explore the science of boundaries, why they can be difficult to establish, and how therapy can help you build healthier, more sustainable relationships.
What Are Boundaries in Relationships?
Boundaries are the guidelines and limits we set in relationships to protect our emotional wellbeing, values, and personal space. They define:
What feels comfortable for us.
What behaviours we accept or won’t accept.
How much emotional, physical, or time investment we can realistically give.
Types of boundaries include:
Emotional boundaries: protecting your feelings and energy.
Physical boundaries: respecting personal space and touch.
Time boundaries: how you allocate your time and commitments.
Digital boundaries: limits around phone, email, or social media use.
Healthy boundaries don’t push people away - they create clarity, safety, and respect.
Why Is Setting Boundaries So Hard?
Even when we know boundaries matter, many people struggle to put them into practice. Research and clinical experience suggest several reasons.
Family Dynamics and Early Conditioning
If you grew up in a family where your needs were ignored, criticised, or overridden, you may have learned that it’s safer to stay quiet, please others, or avoid conflict. In adulthood, this often shows up as difficulty saying “no” or fear of disappointing others.
Fear of Rejection of Guilt
Psychology research shows humans are wired for belonging. Setting a boundary can feel like risking disconnection - even though, paradoxically, boundaries are what allow true closeness.
Guilt and Shame
Saying “I can’t do that” or “That doesn’t work for me” may trigger guilt if you’ve internalised the belief that your worth depends on self-sacrifice or compliance.
Unclear Self-Identity
Without a strong sense of your own values, needs, and priorities, it’s harder to define where you end and others begin.
The Psychology of Boundaries: What Research Shows
Boundaries aren’t just “common sense” - they’re backed by psychology and neuroscience.
Attachment theory: people with secure attachment tend to set healthier boundaries, while those with anxious or avoidant styles may either over-give or withdraw.
Self-determination theory: Research highlights autonomy (the ability to make choices aligned with our values) as key to wellbeing - and boundaries protect autonomy.
Stress response: Chronic lack of boundaries can lead to heightened cortisol (stress hormone), emotional burnout, and even physical health issues.
How to Start Setting Healthy Boundaries
If boundary-setting feels overwhelming, start small.
Evidence-based approaches often used in therapy include:
Identify Your Needs
Journaling, therapy, or mindfulness can help you tune into what feels draining versus energising.
Use Clear, Simple Language
Instead of long justifications, try:
“I can’t commit to that right now.”
“I need some time for myself this evening”
“Please don’t comment on my body”
Practice Tolerating Discomfort
Boundaries can trigger temporary awkwardness - but over time, relationships adapt, and respect grows.
Seek Support in Therapy
Therapy offers a safe, non-judgemental space to explore why boundaries are difficult and prioritise new ways of communicating. Modalities like Cognitive Behavioural Therapy (CBT), Schema Therapy, or Psychodynamic Therapy often explore patterns around people-pleasing, guilt, or self-worth.
How Therapy Helps with Boundaries
Working with a therapist can:
Uncover the root causes of boundary struggles (family dynamics, attachment patterns, cultural expectations).
Provide tools and language to express boundaries clearly. \Help you practice new behaviours in a safe space before using them in real life.
Support you in processing the guilt, fear, or shame that arises when you start setting limits.
Boundaries are not about shutting people out - they’re about creating relationships where both people feel safe, respected, and authentic.
Boundaries as Self-Compassion
Setting boundaries can feel difficult, especially if it hasn’t been modelled for you. But far from being selfish, boundaries are an act of self-compassion. They allow you to show up fully in your relationships without resentment, exhaustion, or burnout.
If you find it hard to set limits or notice yourself stuck in people-pleasing patterns, therapy can help you explore why - and give you the skills to change.
✨ At Smart Therapy in South West London, our therapists offer supportive, evidence-based counselling to help you build healthier boundaries, relationships, and self-worth.
