Neville has some separation anxiety. When we first got him, he chewed his way out of two crates. He got his jaws around the bars and squeezed them together til they broke.

We called him "Dogzilla." He seems to be fine when he shares a crate with Luna. He has stayed with my parents a couple of times and didn't have a problem. They have a dog about his size and the two of them like to "fight" over the squeak toys. But the longest we've left him is a week, and he's never been to a boarding facility. Mom and Dad vetoed taking him for three weeks, so he has to board with the rest of the gang.
Juanita is just generally scared of everything. I've been taking her to as many places as I can, trying to desensitize her to strange situations and noises, being held by others, and taking treats from them. She's so skittish, even I have trouble getting her to come to me or letting me pick her up. We have a little ritual we have to do - she goes to her crate and I can pick her up from in there. She's made a lot of improvement since November when I got her, but she still has a way to go.
Fortunately they both love Luna, and Luna loves to go to the doggie hotel. She's going to go to day-care with them. I'm hoping that once they get to know the staff they'll be okay. They tend to get spoiled rotten at this place - Luna actually pouts when she has to come home - and I know Neville and Juanita will get extra attention b/c of their "problems." I'm just afraid they'll feel abandoned again with us being away so long.