The couple split in 2008 after almost eight years of marriage, and their divorce was finalized earlier this year.
The director reveals he suffered heartache during their split, but hints that the star was emotionally withdrawn during their time together.
He tells Britain's Esquire magazine, "You can't tell someone when they're getting divorced that their pain is an illusion. I'm f**king telling you, I feel it, I've been through that.
"And, of course, here you go: I still love her. But she's retarded, too."
The quip is seemingly in reference to Madonna's outburst during a gig on her Sticky & Sweet tour just after the split, when she gave a shout-out to the "emotionally retarded," before adding, "You may know a few people like that. God knows I do."
However, Ritchie is also full of praise for the hard-working pop star.
He adds, "She's a manifester, if there ever was one. First-rate manifester. Madonna makes things happen. Put Madonna up against any twenty-three-year-old, she'll outwork them, outdance them, outperform them. The woman is broad."
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