Potters winger compares the loss against Roberto Mancini's side to the defeat he suffered as a West Ham player in the final against Liverpool five years ago
A Yaya Toure strike in the second half secured the tie for Roberto Mancini's side in a game which Stoke struggled to maintain possession.
The 29-year-old left-winger, who was a major doubt before the tie, has been a part of tragic cup finals before, being a member of the West Ham United side five years ago who conceded the lead twice against Liverpool before losing altogether.
But Etherington thinks Stoke's loss against Mancini's side on Saturday was equally hard to take.
"That time I was devastated and just as devastated now, if not more," he told the Press Association.
"To lose it twice is obviously hard to take. To get there and for it not quite to happen is devastating.
"We were poor first half and Man City played well. [They had] Plenty of chances.
"Second half, we were better but it wasn't to be. They've popped up with a goal and hung on in the end."
The former Spurs man felt fortunate just to kick a ball, in the end, after tearing his hamstring just over two weeks ago.
"I hadn't done any training all week, literally hadn't kicked a ball," he revealed.
"I had a grade two tear in my hamstring and I was just happy to be out there, to be honest with you.
"Usually, it's four to six weeks and the medical staff here did wonders with me.
"It was intense treatment with me all day, every day, and I felt good enough.
"I thought I'd ease myself into it and just up until I got took off, I felt as though I was getting in the game.
"It wasn't to be and obviously everyone's devastated."
Stoke face Manchester City again in just two days time in a rescheduled Premier League fixture at Eastlands.