Years ago while vacationing in Finland me and my buddies were partying in the sauna. There was a huge oak barrell outside where you're suppose to submerge after sitting in 110C temperature.
While we were chilling in there all of their wives except for mine came out naked and jumped in. Some of them were related to each other.
My W decided to go to sleep. I hung out until we ran out of beer.
Now seriously. What was she going to do in the Jaccuzi?
I think your reaction was warranted, but the delivery could have been different.
"W, I am not sleepy right now. Do you mind if I sit here and watch for awhile?"