What would you do to decide if you have avoidant personality disorder or a severe case of social phobia?

Severity: These two conditions are close together and they are along a continuum. Avoidant pd is likely very long-term and starting in early adulthood and spanning for decades. Social phobia might be more situation or age specific. Group therapy is good for both of them.

Both dx: My colleague is correct here. I would simply add that many people with a more generalized social phobia (fear of most social situations) have more of an embarrassment response to social situations whereas the majority of people diagnosed with social phobia to specific situations, say public speaking, experience more fear. Generalized social phobia and apd usually diagnosed together.