how to cure a scared/aggressive dog?

[mallorie]

we adopted a golden/sheperd puppy last year and hes always been scared of everyone besides my family. he likes most of my friends and people hes known for awhile but around new people he gets scared and hides. yesterday my moms drunken friend came up to his face and he bit her. now my parents think we need to get rid of him. is there anything you can do to help an unsocial scared dog? i knwo hes not aggresive the only reason he bit was because he was scared. how do you cure this? please help