He took to Intagram and Twitter to express his sorrow at her sudden death, aged only 47.
The 49-year-old performer and music mogul wrote: "For the last three days I've been trying to wake up out of this nightmare. But I haven't. I don't know what I'm going to do without you baby. I miss you so much. Today I'm going to pay tribute to you, I'm going to try and find the words to explain our unexplainable relationship.
"WE WERE SOME OTHER SHIT!! And I miss you so much. Super Black Love."
The pair had been a couple for 13 years and they were still on good terms right up to her death.
They shared three children together – 11-year-old twin daughters Jessie James and D'Lila – and son Christian Combs, 20.
Diddy's representative Cindi Berger confirmed on Thursday that Porter had died.
"Sadly, I can confirm the passing of Kim Porter. I ask that you give the families privacy at this time," she said.
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Sources revealed police rushed to Porter's Los Angeles home after receiving a 911 call over a reported 'patient in cardiac arrest'.
The autopsy results have still to be released – Porter also shared a 27-year-old son Quincy from her previous relationship with R&B singer Al B. Sure!
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