What OCD actually is
Obsessions are unwanted intrusive thoughts, images or urges that cause distress. Compulsions are mental or physical acts performed to reduce that distress. The compulsion brings short-term relief, which reinforces the cycle. OCD is not about being tidy — it is about the loop.
How ERP works
With a therapist, you build a hierarchy of feared situations, deliberately face them, and resist the compulsion. Anxiety rises, then falls (habituation) or you learn the feared outcome does not occur (inhibitory learning). Over weeks, the loop weakens.
Medication and self-help
SSRIs (often at higher doses than for depression) are effective. Self-help apps and books can supplement but rarely replace structured ERP with a clinician.