Villa skipper Barry admitted there were times during the Sven-Goran Eriksson era when he wondered whether his international days were over.
But the unflagging support from the massed ranks of the Holte End and constant chants of 'Barry for England' ensured Barry never threw in the towel with his country.
Barry said: "There were times when I did wonder if I would play for England again.
"When you are basically overlooked for three or four years, that is bound to cross your mind.
"But the Villa fans certainly played a part in helping me to keep believing through the low points that one day I would get another chance if there was a change of manager.
"It was such a lift to hear them chanting 'Barry for England' every time I was in action on the Villa Park pitch and I thank them so much for their support. They have helped me a lot.
"Now I have got in three or four squads in a row which is a different situation for me and, given what will be at stake, Wednesday will be the biggest game of my career.
"I have played in three games in a row and I am full of confidence now. In international football, you've got to be mentally strong."
Barry is desperate to make the squad for Euro 2008 - if England qualify - after being a non-playing member under Kevin Keegan eight years ago for the tournament in Belgium and Holland.
"He said: "Euro 2000 seems a long time ago. I was only 19. A lot has happened since then. I gained a tiny bit of experience there from being involved in that squad.
"It would be great to go to another tournament and actually play some part. There is still a lot of work to be done to try and help the team qualify for Euro 2008.
"The next step is to stay involved in the games coming up to get us there but then hopefully be selected to go to Austria and Switzerland next summer."