My 10 month old jack russell has bitten 2 people, please help us!

From the day I brought my little guy home I knew he was going to be a handful, much like the half-brother and sister he has at my parents house were as puppies, but I had no idea to what extent. He began growling at less than 6 months old, and not the playful kind. If I needed to pick him up while he was sleeping he would attack, drawing blood enough times that when he fell asleep on the couch and refused to get up on his own I had to mussel him to carry him to bed. (My, very comfortable, very expensive bed that he gets most of to himself) In roughly 2 months my little Cooper will be turning 1, and has just recently escalated. Both incidents being at my parents house around the 2 other dogs that aren’t very socialized or trained, thankfully neither being serious enough to report or see a doctor. Upon endless hours of research, trial and error, watching his every move and his expressions, all I have accomplished is coming to the conclusion that he is biting out of extreme fear, anxiety, and confusion. The visit to the vet my family has been seeing for over 10 years left me even more hopeless, as he was given generic xanax, told it was genetic, that I needed to be careful, but one day there would come a time I would just have to make ‘a decision’. This little guy means the world to me and it scares me to death thinking about it coming to that. I have tried just about everything but I don’t have the money, time, or location for professional help, but I don’t want him to spend his life on a leash, musseled, or inside to prevent him from biting someone. Advise, recommendations, anything would be so helpful! Please!