If you are committed but Not in an "open" relationship (where you do give each other permission to be intimate with other people) . . . then i don't see how sleeping in the same tent with another woman would be appropriate at all. It's just not.
If there were seperate tents involved, then it would be fine . . . but why the need to sleep in the same small tent? Is there a shortage of tents in the world?
Botton line:
If it's gonna cause stress, then just avoid it.
You and ktspktsp seem to be doing a great job of communicating and obviously are taking each other's feelings into account

Bravo on that

you're a great couple.
Sweetpea