The 33 year-old will leave City at the end of the season when his contract expires. However, the Belgian insists the decision was driven by the club, not him.
He said: "There was a little bit of shock. I didn't have any offer from them through the whole year and the club made a decision.
"Obviously, I was a bit surprised but I have to accept it.
"Honestly, I still think I can perform at this level like I'm showing but I understand that clubs have to make decisions."
He added: "It was half a week till I reported it out and it wasn't nice. My family weren't home.
"They were on holiday so it was a bit weird but it is what it is.
"After the decision was made and when I came out, it was more of a relief when I reported it to the outside world compared to when I knew and nobody else knew.
"You don't know what to do with the emotion with everybody and how to handle it at the club.
"Now it's out, it's fine and people see the way I am. I try to do my best and win games for the team. I love playing football so that's it."
"Maybe a different decision would've been made"
De Bruyne admits his meeting, when he was informed there would be no renewal, with execs Txiki Begiristain and Ferran Soriano was brief. The City legend feels if the team had performed better there would've been a new deal on the table.
He also was quoted by The Sun: "It's basically why they've made the decision because the whole team has struggled.
"Maybe if the team didn't struggle and I came back like I did this year and bedded in like normal then maybe they would take another decision.
"I don't know - they told me what the decision was and I can't really say what they think on the inside.
"I still think that I'm in good shape, I've played way more than I did last year except the hernia. I feel good and the rhythm is coming.
"I don't feel like I want to share (the exact reasons) because it's basically more business-wise for them and they made a decision based on that.
"It was not really a long conversation. It was just what they told me and then there's nothing."