Our dog would be miserable if she was left alone - heck, I leave her for half an hour and she's miserable!

Dogs are pack creatures - they don't do well when they're isolated. It's stressful for them.
So when we travel we either take our dog with us, or we have a friend come and live in our house while we're gone.
My BIL doesn't have a friend who can house sit for him, so he leaves his dog at a kennel. The kennel is very, very nice - big roomy place, a lovely green field to run in, and they group dogs by size and temperament. His dog loves the place and gets excited whenever they drop her off.
I've looked after my neighbour's dog for him when he's travelled - he drops his dog off at my house and she lives with us until he gets back. She's a little sad, but I think she's still a lot happier than she would be sitting at home all alone.
I have another neighbour, however, who will go away for a weekend and just pay my daughter to come over and feed her dog and put the dog outside. Frankly, I don't think this works well, and may have something to do with the fact that she owns one of the most neurotic, messed-up little dogs I've ever met. She complains that the dog leaves "presents" in her bed when she goes away... and I'm thinking, "Gee, I wonder why?"
BTW - our dog travels so well that on occasion we've crossed the border to the US and the agent hasn't even realized she's in the car with us. She flops down on the seat between the kids and looks just like a stuffed animal. (We, of course, always have all the necessary papers - we just don't always get asked for them!)