I think that his behavior must be normal.  I've had a similiar experience.
 
Almost a year ago, I got a female mitt for Christmas.  We already had one
ferret (Seth, or , as we often times call him, Skunka) and we had had him
over a year.  When we brought the new baby in, Skunka started acting
depressed.  Instead of following me around at my heels when I opened his
cage, he would just lay there.  He wouldn't eat because he had to share his
food with Minnie.  He wouldn't play and he wouldn't have anything to do with
Minnie unless he was biting her ears or throat.  He even lost a little
weight.  We took him to the doctor, but there was nothing wrong with him.
After about two months or a little more, Skunka started interacting with
Minnie more and more.  Eventually he started playing with us again.  And
after about 3 months, he was acting normal.  Now you couldn't pry him and
minnie apart with a crobar.  They play, sleep and eat together.  He actually
misses her when we let him out for playtime and not her (she has a small
problem with using a litterbox.  she thinks floors are much better.).
 
I've also heard other ferret owners tell the same stories.  Ferrets are very
intelligent and they get jealous.  I hope this makes you feel better.  I
know you probably feel sorry for little Eddie, but he will have to adjust on
his own.
 
Talk to you later!
 
April
Skunka (Pleeeeese scratch my head... then give me chocolate!)
Minnie (OOOh, a plastic bag.  I wonder what's inside?)
[Posted in FML issue 2104]