Good afternoon. Welcome to JA.
Mythomania is otherwise known as "compulsive, pathological, or habitual lying." Mythomania is not a psychological/psychiatric disorder per se. Rather it could be considered a symptom of a broader mental disorder such as a Substance/Alcohol Abuse Disorder, a personality disorder (such as Antisocial Personality Disorder, Narcissistic PD, Borderline PD), or even some of the more "common" disorders like Anxiety or Depression.
While you *may* find someone who specializes in treating compulsive or pathological lying (Mythomania), you are more likely to find someone who specializes in the treatment of broader mental disorders (like those listed above).
Given that Mythomania is not a disorder per se, it may be worthwhile to explore a Psychological Evaluation to see if there are broader patterns that might be more reflective of a recognized disorder. A Clinical Psychologist or Psychiatrist can provide one of these.
I hope this was helpful. Best of luck to you.
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