Karen Bardsley will retire at the end of the season after 13 years at the top of the women's game.
She won eight major trophies with City, including their first Women's Super League title.
Bardsley has struggled for game time since he picked up a injury at the World Cup.
She said she wanted people to know she always gave her best.
The last league match Bardsley played for City was against Villa.
When your body doesn't match what you want to do, it's frustrating.
The risks were greater than the rewards in terms of life after football. If I had to go through another surgery like the ones I have been through, I don't think it would be good for me.
Retirement was a difficult one to accept. I wouldn't be able to get a word out if I had this conversation a few years ago.
I tried to be the best leader and goalkeeper I could be.
Bardsley played in three World Cups and two European Championships for England.
She played in the 2012 Olympics for Team Britain, who lost 2-0 to Canada in the last eight.
Bardsley has been at Manchester City for four years, winning four League Cups and three FA Cups.
She said that winning the League Cup final in her first season with Man City was one of the most meaningful experiences in her life.
We were a ragtag group of girls that got thrown together. Nobody expected anything from us.
We all came together as a group, and I remember that first goal, I just couldn't believe it was happening.
Everything we wanted to happen was solidified by it. It was a great start to the club's history.
The US-born keeper said she was proud to be a part of an England side that would break through some historical barriers.
Bardsley said it was an honor to be part of a community of amazingly talented female athletes that have persevered through situations where they haven't really had the respect that they deserve.
We have built and built, and now we are in a place where young girls can join a grassroots football club and aspire to be a Lioness or professional footballer.
Bardsley began her career in the US at Sky Blue FC before moving to Sweden with Linkopings. She moved to the WSL side Lincoln City Ladies in the summer of 2013).
She signed a one-year contract extension with City in July after spending last season on a US side.
Bardsley is already looking to the next stage of her career and wants to use her experience to help grow participation of girls playing football.
She said that she was excited about giving people the best chance to fulfill their potential, whether that was in football or another environment.
I want to give back to football and the goalkeeping community in particular. There are a lot of things I would do differently if I were a young goalkeeper.