The Owls chief lost his first match since taking over in February at the hands of his firmer club as late goals from Albert Adomah and Tammy Abraham sealed the points for Dean Smith's side.
Wednesday had taken the lead in the first half as Gary Hooper tapped home from George Boyd's cross, but Villa were level before the break as John McGinn’s impressive finish went rifling past Westwood.
The turning point in the game came as Steven Fletcher missed a penalty, before the visitors punished the Owls in added time with two late strikes.
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But Bruce was pleased with his team despite the result, as he said: “Well I have been in it a long time and it is cruel at times. You don’t get what you deserve and certainly today was one of those days where that happened.
“Especially the second half, it was a bit of an onslaught and we just needed that break which never came unfortunately.
“In terms of the way we played I couldn’t have asked for anything more and on another day you win the game which is obviously what we wanted to achieve.
“As we have seen today, the results, I’ve took a glimpse of them and I’ve shook my head when I have seen them so you can never say never.
“But six points is probably going to be too much to make up in the six games but you can never give up the ghost.”
The afternoon's results leave Wednesday in 12th place in the league table, now six points off the top six on a tough afternoon for Bruce's side.
“The way we went about our work today was admirable,” he said. “They needed and deserved a break and it would have been great to get the result because that would have put us right in amongst it but unfortunately that wasn’t to be.
“That didn’t really help at all, it was the players on the pitch who went about what they did and we have got some good players ourselves and a couple of times it has whistled past the post by two or three inches.
“Of course the big turning point in the game is the penalty and arguably the best player since I have been here in Fletcher has missed it.
“In big moments and big games you need to take them chances and unfortunately we haven’t been able to take them.”