I definately got the feeling that Matt and Amy want different things to happen in their future. Amy seems to want to travel where Matt doesn't - although I can't blame him because its hard for him to get around.
I think Matt does what he wants to do.
Matt went to Iraq twice-and those weren't comfortable conditions.
Amy wants to experience things with her kids, travel etc.,
Matt likes to plan things at home with his kids.
He did that car trip and picked up the VW Beattle and had it restored with the boys.
I think both of them have to give/take in their relationship. It's horrible to go on a vacation with someone, and have them doing work, ie, the cruise down the Mississippi last year. But remember Matt and Amy went on a cruise last year the start of pumpkin season? it wasn't even on the show.
Makes you wonder what is going on, plus after Jon and Kate's fiasco show, TLC, can make it look this way too. Matt made a face after he told Amy it is okay if she goes to Spain with the kids, then he made a really bad face of contempt.