Rocklin
Photo of Dr. Thalia P. Sullivan Nicholson, Psychologist, PhD
Dr. Thalia P. Sullivan Nicholson
Psychologist, PhD
Email Me
(530) 423-3714 Call Me
(530) 423-3714 Call Me
or
Email Me
Photo of Dr. Thalia P. Sullivan Nicholson, Psychologist, PhD

Dr. Thalia P. Sullivan Nicholson

Psychologist, PhD

Verified by Psychology Today Verified by Psychology Today
3 Endorsed
Call Me
Let's Connect (530) 423-3714
Photo of Dr. Thalia P. Sullivan Nicholson, Psychologist, PhD
Available both in-person and online
5701 Lonetreet Blvd Suite 113 Rocklin, CA 95765
My website
Do you feel like you are constantly on edge or just going through the motions? The weight of what you have experienced might show up as sleepless nights, a short fuse, or feeling shut down and disconnected from those you care about. Guilt, intrusive thoughts, or that relentless “always on alert” feeling can take over—but you don’t have to stay stuck in that cycle. My style is goal-oriented, time-efficient, & focused on results without keeping you in therapy any longer than necessary! Together, we will build a clear and practical plan to help you feel better, regain balance and control, and function at your best on and off the job.
A calm, private space for in-person sessions in Rocklin, CA.
I work with first responders, active-duty service members, veterans, high-stress professionals, and their families to address the mental, physical, and behavioral impact of trauma. I also treat related concerns such as panic attacks, anxiety, depression, insomnia, and burnout, providing structured care designed to improve overall well-being and performance.
For those wanting faster results, I offer Models of Accelerated Service Delivery (MASD)—focused, high-frequency therapy designed to create progress in weeks, not months. I also provide psychological assessments, pre-employment and fitness-for-duty evals, and agency consultation. If you’re ready for therapy that works as hard as you do, let’s start today!
Call or Dr. Thalia P. Sullivan Nicholson now for a free 15 minute consultation - (530) 423-3714

My Practice at a Glance

Available both in-person and online

5701 Lonetreet Blvd

Suite 113

Rocklin, CA 95765 map

 (530) 423-3714

Reno, NV 89512

My website
In-person and online therapy in California & Nevada with hours designed for those with shift work and demanding, unpredictable schedules.
I specialize in Trauma and PTSD, Veterans and First Responders 
$225 Per Session  
I see individuals and couples  
Let's Connect (530) 423-3714
Photo of Dr. Thalia P. Sullivan Nicholson, Psychologist, PhD

My Practice at a Glance

Available both in-person and online

5701 Lonetreet Blvd

Suite 113

Rocklin, CA 95765 map

 (530) 423-3714

Reno, NV 89512

My website
In-person and online therapy in California & Nevada with hours designed for those with shift work and demanding, unpredictable schedules.
I specialize in Trauma and PTSD, Veterans and First Responders 
$225 Per Session  
I see individuals and couples  

Finances

Fees

  • Individual Sessions $225
  • Couple Sessions $275
  • Sliding scale: apply if you may be eligible

Payment Methods

American Express, Discover, Health Savings Account, Mastercard, Visa

Insurance

  • Out of Network
"
A superbill can be provided for out-of-network reimbursement. Sliding scale and pro bono options may be available. Assessment and consultation fees vary based on service complexity. Please contact me directly for a tailored estimate.
Photo of Dr. Thalia P. Sullivan Nicholson, Psychologist, PhD
Dr. Thalia P. Sullivan Nicholson
Psychologist, PhD
Call or for a free 15 minute consultation now - (530) 423-3714
"
A superbill can be provided for out-of-network reimbursement. Sliding scale and pro bono options may be available. Assessment and consultation fees vary based on service complexity. Please contact me directly for a tailored estimate.
Photo of Dr. Thalia P. Sullivan Nicholson, Psychologist, PhD
Dr. Thalia P. Sullivan Nicholson
Psychologist, PhD
Call or for a free 15 minute consultation now - (530) 423-3714

Qualifications

  • Verified by Psychology Today Licensed by State of California / 35995 Thalia Pitsillidou Sullivan Nicholson

    • Education and Years In Practice

  • Attended East Tennessee State University, PhD in Clinical Psychology, Graduated 2024

    • Additional Credentials

  • Certificate from Cognitive Processing Therapy-Veterans Health Administration 2025
  • Certificate from Motivational Interviewing-Veterans Health Administration 2024
"
I'm a licensed psychologist with a PhD in Clinical Psychology. I completed residency at the Sacramento VA and fellowship at the Martinez VA & Travis AFB. I specialize in trauma-focused care for first responders, military, and frontline professionals, with additional focus on serving rural folks.
Photo of Dr. Thalia P. Sullivan Nicholson, Psychologist, PhD
Dr. Thalia P. Sullivan Nicholson
Psychologist, PhD
Call or for a free 15 minute consultation now - (530) 423-3714
"
I'm a licensed psychologist with a PhD in Clinical Psychology. I completed residency at the Sacramento VA and fellowship at the Martinez VA & Travis AFB. I specialize in trauma-focused care for first responders, military, and frontline professionals, with additional focus on serving rural folks.
Photo of Dr. Thalia P. Sullivan Nicholson, Psychologist, PhD
Dr. Thalia P. Sullivan Nicholson
Psychologist, PhD
Call or for a free 15 minute consultation now - (530) 423-3714

Specialties and Expertise

Top Specialties

  • Trauma and PTSD
  • Veterans
  • First Responders

Expertise

  • Alcohol Use
  • Anxiety
  • Chronic Pain
  • Depression
  • Family Conflict
  • Grief
  • Mood Disorders
  • Sexual Abuse
  • Sleep or Insomnia
  • Stress
  • Substance Use
  • Suicidal Ideation
  • Testing and Evaluation
"
If you want a psychologist with both personal and professional experience in first responder and military culture, I can help. My background spans the VA, USAF Medical Center, and direct work with departments, all focused on building resilience and supporting both those who serve and their families.
Photo of Dr. Thalia P. Sullivan Nicholson, Psychologist, PhD
Dr. Thalia P. Sullivan Nicholson
Psychologist, PhD
Call or for a free 15 minute consultation now - (530) 423-3714
"
If you want a psychologist with both personal and professional experience in first responder and military culture, I can help. My background spans the VA, USAF Medical Center, and direct work with departments, all focused on building resilience and supporting both those who serve and their families.
Photo of Dr. Thalia P. Sullivan Nicholson, Psychologist, PhD
Dr. Thalia P. Sullivan Nicholson
Psychologist, PhD
Call or for a free 15 minute consultation now - (530) 423-3714

3 Endorsements

Courtney L Cook
Courtney L Cook
Psychologist, PhD, HSP
Dr. Thalia Nicholson is an excellent psychologist with a passion for supporting first responders and veterans. Not only is she highly skilled, she is genuine, compassionate, and warm. I highly recommend her!
Brittany Thomas-Vestal
Brittany Thomas-Vestal
Clinical Social Work/Therapist, LCSW
Dr. Thalia Nicholson is an incredible asset to the first responder community. Her knowledge, compassion, and deep cultural competence make her one of the most trusted and authentic professionals I'm proud to refer to often.
Dr. Larissa Tate
Dr. Larissa Tate
Psychologist, PhD, HSP
Dr. Nicholson is not only an expert in her field, but is incredibly grounded, compassionate, and thoughtful. She provides her clients with high-quality, effective therapy that helps them get back to their best. I recommend her highly!

Client Focus

Age

Adults , 
Elders (65+)

Participants

Individuals , 
Couples

I also speak

Greek

Age

Adults , 
Elders (65+)

Participants

Individuals , 
Couples

I also speak

Greek

Treatment Approach

Types of Therapy

  • Acceptance and Commitment (ACT)
  • Cognitive Behavioral (CBT)
  • Cognitive Behavioral Conjoint Therapy for PTSD
  • Cognitive Processing (CPT)
  • Culturally Sensitive
  • Exposure Response Prevention (ERP)
  • Forensic Psychology
  • Motivational Interviewing
  • Prolonged Exposure Therapy
  • Psychological Testing and Evaluation
  • Solution Focused Brief (SFBT)
  • Trauma Focused
  • Written Exposure Therapy (WET)
"
I provide evidence-based psychotherapy focused on the treatment of posttraumatic stress, as well as co-occurring conditions such as panic disorder, generalized anxiety disorder, depression, insomnia, and chronic pain. All treatments are grounded in research-supported approaches and delivered through a culturally competent, trauma-informed lens.
Photo of Dr. Thalia P. Sullivan Nicholson, Psychologist, PhD
Dr. Thalia P. Sullivan Nicholson
Psychologist, PhD
Call or for a free 15 minute consultation now - (530) 423-3714
"
I provide evidence-based psychotherapy focused on the treatment of posttraumatic stress, as well as co-occurring conditions such as panic disorder, generalized anxiety disorder, depression, insomnia, and chronic pain. All treatments are grounded in research-supported approaches and delivered through a culturally competent, trauma-informed lens.
Photo of Dr. Thalia P. Sullivan Nicholson, Psychologist, PhD
Dr. Thalia P. Sullivan Nicholson
Psychologist, PhD
Call or for a free 15 minute consultation now - (530) 423-3714

Location

Primary Location

5701 Lonetreet Blvd

Suite 113

Rocklin, CA 95765

(530) 423-3714

Email Me

My website

Additional Location

Reno, NV 89512

(530) 423-3714

Nearby Areas

Cities

Counties

Zips

Neighborhoods

"
In-person and online therapy in California & Nevada with hours designed for those with shift work and demanding, unpredictable schedules.
Photo of Dr. Thalia P. Sullivan Nicholson, Psychologist, PhD
Dr. Thalia P. Sullivan Nicholson
Psychologist, PhD
Call for a free consultation now - (530) 423-3714
"
In-person and online therapy in California & Nevada with hours designed for those with shift work and demanding, unpredictable schedules.
Photo of Dr. Thalia P. Sullivan Nicholson, Psychologist, PhD
Dr. Thalia P. Sullivan Nicholson
Psychologist, PhD
Call for a free consultation now - (530) 423-3714