I believe it is The Vacuum-Packed Picnic by Rick Gauger
It features a picnic on the lunar surface, which leads to the original poster's tryst:
“A picnic. How would you like to go on a picnic? With me,” I said, blurting out the first idiocy that came into my mind. “If you like, I’ll take you to one of my favorite spots. It’s not far, just a short walk from the base.”
Her reaction was everything I could have hoped for. Her delicate mouth dropped open a little. “You’re kidding. An outdoor picnic?”
“Why, sure,” I lied. “It’s a new recreation we’ve come up with here on the moon.
It features a vacuum-proof tent-dome:
You know what survival tents are. They’re what’s inside those emergency boxes you see everywhere on the moon.
They take two, link them together, and have an "encounter" in one, leaving clothes/dishes in the other:
“Now I can give you the attention you deserve,”
(I decided to keep that part safe for work.)
The two bubbles come apart from each other, which is what went 'awry', leaving them nude in one, and their clothes/dishes in the other:
The other tent, the one with our stuff in it, had become detached from the tent we were in. The two door gaskets had separated, the air had escaped, and now the other tent was lying collapsed over our suits, our helmets, our boots, our underwear, the food container, Stacy’s backpack, the dirty dishes. All of it was out there in the clean, fresh vacuum I had been talking about. We were left buck -naked in the tent, with nothing but the blankets and my backpack.
They then have to return home by 'rolling' the bubble:
“Try to shuffle your feet toward the edge of the floor,” I said. The tent slowly rolled onto its side, the scraps of blanket sliding downward as the tent floor tilted upward. The rim of the tent flattened on the ground. It was like standing inside a -huge flat tire.