Just putting this out here in case anyone can help me, though I suspect not.
My wife and I have had a rather neurotic Jack Russell terrier, Gary The Wonder Dog, for the last couple of years — he’s eleven or twelve, but we adopted him because of family stuff, so he was pretty set in his ways when we got him.
He’s a great little dog, with only two real flaws (and one of them can be solved by just never giving him Dentastix). The one that can’t be fixed is that he gets terrified he’s being abandoned when I go to bed every night — he practically has a panic attack more nights than not, and this distresses both of us. (He never gets like that when alone at other times — he’s actually a rather standoffish dog who likes his personal space — just bedtime.)
Now the obvious solution to that would be to let him in the bed with us. But while he’s OK in bed with just Holly, if I try to get into the bed he’ll get incredibly territorial, snarl, snap, and generally make it impossible for anyone to rest.
We can’t put his bed in the bedroom, because then he just jumps onto the bed. Does anyone have a suggestion for any way I can actually go to bed without causing my dog unnecessary distress?
Sci-Ence! Justice Leak! 
Are you sure he’s having a panic attack because you’re leaving him, and not because he’s worried you’re going to steal his territory (the bed)?
How does it manifest?
He scrabbles his paws at my legs to get me to pick him up as I’m going to bed, and if I bend down to try to calm him he’ll sometimes clamp my arm in his forelegs and not let go. He’s fine if I pick him up and carry him, but gets upset again when he’s put down. He’ll sometimes whine when I shut the living room door with him inside. (This is still better than he was when we first got him, when he would actually howl).
If he’s allowed into the bed, *then* he worries I’m stealing his territory, and acts accordingly (snarling, making a face like a xenomorph, snapping, etc).
Firstly, according to my son who has a much loved Jack Russell, Gary is a very old man. This being the case, forcing him to change may not be safe.
But I understand how difficult this may be. We once had a rescued dog, (wire haired terrier crossed with a retriever, we think) who was a great house-dog and family pet, but who thought that his mission in life was to kill everything else on four legs, which made walks very exciting for 14 years! The rescue centre that he was in before we took him, (which friends of mine had volunteered for), turned out not to be as good as we all thought, and was closed down about a year later. It appears, among other things, that the dogs were kept in group pens where they had to fight for food. Dogs have very long memories.
So to understand Gary’s problem you may have to find out what happened to him, or what his bedtime routine was, before you took him over.
If his problem is simply that he feels insecure, you could buy a travelling cage and encourage him to use it instead of a dog bed during the day. (Don’t close the door, and make him feel trapped.) You might find that his new, more sheltered bed, with only one access point that he can watch will give him the security, and perhaps warmth, he wants. If it doesn’t, and he still panics, you could try using it with the door closed to go on outings that he enjoys, and when he is used to that try shutting him in at night. You could try taking the travel cage into your bedroom to make it a pleasanter experience for him.
But don’t rely on what I say working,. Remember that I failed to modify Bounce’s problem for 14 years!
But best wishes to Gary from us and my son’s 8-year-old Jack Russell Kai!