The veteran striker suffered a serious knee injury for Manchester United last week and is expected to be out of action for quite some time.
Despite the prospect of missing months and months of football at the age of 35, Mourinho expects the hard-working Swede to come out the other end an even stronger person.
"The future is a big surgery and a long period of recovering. But the future is also in the hands of a very strong guy, mentally very strong, who wrote immediately on social media that he will stop [playing] when he wants, not when people think," said Mourinho.
"It looks for me that he's not going to give up and he's going to fight. I'm really pleased with that because this is the Zlatan I know.
"He fought all his life and that's what I told him - 'you have fought all your life since you were born.' I don't see a reason not to fight."
Ibrahimovic will undergo surgery and begin his recovery in the USA and Mourinho is expecting everything to go smoothly.
He added: "We think he is in fabulous hands and [he needs to] recover from the injury and prepare himself mentally for the next step.
"I think the next step will always be something that he really wants, which is something I was saying before the injury in the period of doubt about his future; I have always said that.
"He is much more important than myself and what I want, it's what he wants. I always want the players to be happy and to choose their future, and this is what I think is going to happen.
"Now, before such an important surgery, I think it's a waste of time to speak about what's next."