Corri, Honestly, to me, it sounds like it was a case of the jitters at the newness of it all...integrating bf into your kids' lives in a way that you had not attempted before.
My first reaction was that I wouldn't let paper-thin walls deter me, but then my next thought was "what if it were my *boyfriend* instead of their dad?" and "what if they were hypersensitive to the possibility of us being too lovey dovey?" and on and on. I think this adds a whole new element to it.
Really...my opinion about vacation is that kids are so wiped out at the end of the day that they are not going to hear/wake up. On the other hand, I can see where their presence and coughs and rolls would unnerve you both, since that is not a dynamic that has come up in your R yet. This was a big first step, eh! It'll get easier and better as time goes on and you build on what you have already endured together.
But back to your original question...I can't really say there are distinct Modes that I am in. I am not, by nature, a moody person--I'm usually very consistent (with the obvious exception being pregnancy, which I had to get in before Hairy does). I find it difficult to switch back and forth but I do take hornypot underground in front of my kids. It is WAY more discreet and secretive but not absent.
So I suppose the answer you are truly looking for is that it is acceptable and even necessary to tone it down when in front of your kids and I'm sure your bf sees the necessity of that. In addition, I'm sure he's a-okay with it so long as you don't forget about him entirely when with the kids. If you did this last vacation, just chalk it up to nerves and first time jitters and STOP WORRYING!
