I’m glad you are asking for some feedback and taking the time to understand your emotional landscape. Of course I can’t make a diagnosis — that is something I am going to encourage you to seek through an evaluation
— but you have highlighted several symptoms that may be part of a larger pattern.
- Drastic appearance changes
- Antisocial behavior
- Aversion to touch
- Impulsive decisions
- Intimacy problems
- Lack of empathy
- Sudden mood swings
- Regressive behavior
- Excessive spending
- Early molestation
- Sibling with a biochemical disorder
Each of these factors points toward the need for a thorough evaluation. A good neuropsychologist can do a series of tests designed to identify various conditions. Many of the tests are objective (some even computerized.) So the answers do not have to be interpreted by another individual. The examiner reviews all the tests and together the battery can give a more complete picture of your strengths and issues. Other psychologists may be able to do this type of testing as well. In any case, such testing can help make sense of seemingly disparate symptoms. You may find someone capable of doing these kinds of tests from this list, but a more direct approach is to use your university counseling center. The professionals there are usually very well versed in both testing and counseling, with professional contacts in the local community. The service is typically free or very low fee. I would begin with a call to them. They might also be able to help set up a psychiatric evaluation for the purpose of determining if medicine is warranted.
You may also want to learn more about your brother’s condition here.
A diagnosis is only helpful if it aids in the process of treatment. The goal is to understand what these symptoms indicate, and to begin coping with them directly. In the words of Martin H. Fischer, “diagnosis is not the end, but the beginning of practice.”
Wishing you patience and peace,