Mariana Nibley, DNP, ARNP, PMHNP-BC

Behavioral Health
Primary Care Freeland & Walk-In Clinic Oak Harbor

Dr. Nibley (she/her/they/them) is a psychiatric/mental health nurse practitioner with experience working with adolescents and adults suffering from varying mental health conditions. Her goal is to treat the holistic patient, rather than a specific disorder or diagnosis, and work with patients to find the most appropriate treatment plan aligning with their goals.

Patient Care Philosophy

  • Build trust with patient to allow for therapeutic alliance (this is a two-way street in which she must respect and believe her patients too!), and utilize family relationships to support and provide additional perspectives regarding their loved one’s  mental health symptoms.
  • Honor patients by utilizing the least invasive treatments and working within their abilities and/or limitations.
  • Address underlying cause(s) of mental health symptoms (physical ailments, trauma, environmental exposures, maladaptive behaviors, ineffective coping mechanisms) to improve outcomes and prevent worsening of symptoms.
  • Find positive coping strategies and community to support growth and progress.

Scope of Care

  • Mood disorders
  • Anxiety disorders
  • Obsessive Compulsive and related disorders
  • Schizophrenia Spectrum and Psychotic disorders
  • Sleep-wake disorders
  • Trauma and Stressor related disorders
  • Substance-Related and Addictive disorders (outpatient)
  • Feeding and Eating disorders
  • Somatic Symptom and related disorders
  • Sexual Dysfunctions
  • Gender Dysphoria
  • Disruptive, Impulse-Control, and Conduct disorders
  • Neurocognitive disorders
  • Dissociative disorders
  • Neurodevelopmental disorders


  • Associates Degree: Nursing: Utah Valley University, Orem, UT 2013
  • Bachelors Degree: Bachelor of Science in Nursing: Utah Valley University, Orem, UT 2014
  • Doctorate: Doctor of Nursing Practice: University of Utah, Salt Lake City, UT 2020

Internship & Residency

  • Psychotherapy practicum at Utah Pride Center (Salt Lake City, UT) working with LGBTQIA+ individuals providing psychotherapy, as well as leading a Women’s Support Group, Transgender Support Group, and Youth Survivors of Suicide Attempt Group
  • Medication management practicum at Fourth Street Clinic (Salt Lake City, UT) serving underprivileged and houseless adults suffering from serious and persistent mental illness.


  • Board Certified by the American Nurses Credentialing Center (ANCC)


Dr. Nibley enjoys connecting with nature and spending time outdoors, including playing sports, hiking, beachcombing, and working in the yard. She is a beginner woodworker and spends time with her family in building a homestead to live a more environmentally sustainable lifestyle, although she does have a passion for television and dabbles with gaming. With her son, Dr. Nibley is developing her whistling and jingle-writing skills, although she won’t be quitting her day job for these hobbies.