What bloody bastards >:\ You study you're ass off and get the qualifications then they won't hire you??? makes it worst that people think you are lying and a drug dealer :\ WTF?
You are being discriminated for you're age and sex, but also not getting volunteer positions is just sad. Stuff all those people who doubt you, they will get run down by a bus or something...I don't know if you have much money for a lawyer or getting advice from them??
If it honestly doesn't work out(and i am sorry for saying this but it's a big IF) have you considered teaching, since you're an honors student you should be able2right?