Hi there...Congrats on your new baby...From what I know of separation anxiety, the one this you don't want to do is make a big deal when you have to leave. This sets them up for problems seperating from you.
Chewy is from a pet store...More then likely a Puppy Mill. I didn't leave him for a few months because we live out in the sticks and to go any where would be too long a time for a young puppy... WHen I finally did leave him I just put him in his create and didn't even make eye cantact with him, he whined and it broke my heart but i was so matter of fact. I also TRY not to make to big a deal when I come back...It is SO HARD to leave them! I would put him in his create or where ever it is you leave him for short times while your home to get him used to being away from you... I do this some times when I need to go upstairs to clean or shower... I never leave him more then a hour or so while I'm home but it helps him see I am coming back!!! Hope this helps!