hi.. my 16 yr old brother has a case of Autism... its not severe but when he went to a Psychiatrist they automatically knew... my mom is always depressed and i cant stand sitting back and watching all of it... my dad is always mad at him and cant stand him.. but my brother has this friend from tennesee that he met online and has been talking to him for 2 years.. and he always says that he "hates this place" and that he wants to move to tennessee... i went on websites looking up stuff about Autism and what it means and the symptoms.. and i looked at pages and pages of stuff and like ALOT of it was exactly like my brother.. just like tons of little things.. and my brother has like 1 best friend.. and they dont even talk anymore.. its amazing how smart he is with computers but besides that he has trouble with math, reading comprehension, and civics... and just alot of things. hes been through sooo many schools ever since he hit a certain age.. and now hes home schooled. he has no plans for his future and when my dad gives him chances to make money he turns it down.. he doesnt do his work.. and he doesnt want to go to college... he also has this diet.. hes a "vegen" he eats ALL natural foods and no animal products... i dont know why he just suddenely changed his state of mind... but i hate it because everytime someone is eating something that is "against his diet" he yells at them and tells them that he hates them and everything that he says he ALWAYS has to be right.. no one can tell him any different so sometimes i just ignore him.. and i know that one day when im older he will probably be living with me.. but i will always welcome him with open arms because i care about him... but i hope that it doesnt come down to that.. and i hope he gets through this stage in life and overcomes Autism.. and moves on in life and becomes succesfull...
if anyone can relate to me or knows what i am feeling PLEASE help... please...
sincerely,
worried sibling

Just as an FYI, autism isn't "curable", he won't be able to "overcome" it and go on to " live a normal life".

What he CAN do however is learn to live with it, and if nutritional intolerances etc. aggravate his problems then some nutritional inteverentions may be of help.

Since he is a vegan, and presumably prepares a lot of his food fresh anyway, it should not be too much trouble trying out something along the Feingold diet (elimination of additives etc. from his diet) for example.

Social training, therapy and counselling with someone familiar with autism may also help.

In some cases where depression, anxiety, concentration problems or aggression are a severe problem, some medication may help.

I'd recommend you read up on the subject, have a look for books on Asperger Syndrome and High Functioning Autism (since it does sound like he is quite high-functioning), there are some especially for relatives, and others for teenagers with these conditions.