My 3-1/2 yr old German Shepherd Dog is wrongly trained into feeding by hand & won't eat by himself. Need Help!

My male egoistic GSD has always been pampered by my wife into hand-feeding. He would never eat on his own. But now we are in a terrible mess as she and our son left today for her annual planned holiday, with both of us thinking that I would be hand-feeding him like I did on every vacation of hers for the last two years (he's three and a half now). But today, the first day, I had a big surprise waiting for me. When I approached with my hand full of food, he snarled at me so fearsomely I was scared he would grab at my hand so I let him be. Incidentally, of late he has been showing traits of irritable temperament due to his adolescence (the vets tell me this is normal and he would tide over!). For the first time I decided to leave him with the food & move away hoping he may eat himself when hungry. But what if he doesn't? Will his separation anxiety (from my wife) and his ego deter him from seeing reason and then will he die of hunger because he is not being hand-fed?