Separation anxiety in my dog?

I have a 1.5yr old beagle boy that I adopted from a family when he was 4 months old, who had gotten him from a breeder. When I got him he was a whiner, but most puppies are I figured. We did crate training which went like it should , but I am always home , I am a stay at home mom, so he never really had to be w/o me. Well , when my oldest son started back at school I started going to teh bus stop and I brought Max with us. As soon as my son would get on teh bus, our dog lost it. That was teh first day of a very long year. My kids cannot be out of site if we are not in our home. I cannot be out of site EVER!! He follows me to every room , and freaks if he even thinks i might be leaving. I have tried everything teh vet has suggested, the whole pretending to leave, do things like carry myu keys os teh noise is not me leaving , crate hom when i am gone, which when i di crate him he drools constantly and chews the wire , and just recently started chewing his leg while I am gone. I tried doggy day care, yet he wont eat and he contantly tries to escape. He has chewed many blinds , trying to get out teh window to me, he wont eat anything when i am gone not even his fav treats or even wet food. In his kennel he pushes teh blankets to one side and drools on teh other. He howls and bellows like no other if he cant find me. I have not tried teh prozac route. I just keep thinking it cant be healthy for him to be this stressed all the time. We have a kitten so hes never really alone, but if he cant find me he terrorizes her now. Its just crazyness help me