Evaluations can usually be completed by a psychologist, psychiatrist or any other mental health professional trained to give diagnoses. You may want to search for a professional who specializes in autism spectrum disorders among adults. You can do this by calling mental health professionals and asking them directly about their specialties. A Google search might help you locate a specialist or your current therapist may be able to provide you with a referral.
Asperger’s is not a fully understood disorder. Characteristics of the disorder include social awkwardness, limited empathy and physical clumsiness. It is considered a mild form of autism. A recent New York Times article reports that in the newest edition of the Diagnostic and Statistical Manual (DSM-V) of psychiatric diagnoses (final version expected in May 2012), Asperger’s disorder may be eliminated and included under the broad-based new diagnostic category of “autism spectrum disorder.” At this time, there is an ongoing debate about exactly what constitutes Asperger’s disorder. If you would like to read more about this topic please click here to read the NYT article that I referenced above.
Being on the “spectrum” is one possible explanation of your symptoms. Other possibilities to consider include schizotypal personality disorder, generalized anxiety disorder or social phobia. It may also be that you simply never learned the proper social skills or you are better at socializing than you may realize. Without more information I cannot know for certain what your diagnosis is and that is why having an evaluation with a specialist is the best way to determine whether you have Asperger’s or another disorder.
The most important aspect of your situation, as I see it, is that you have support and treatment if it’s needed. As you said, you are able to live on your own, but having depression and struggling with the inability to connect with others has to be difficult. I hope you are able to find the help you are looking for. Thank you for your question.