For the first time since Kim Porter and Sean "Diddy" Combs broke up in July, she is speaking – and quite openly – about the split.

Confirming to Essence.com that, despite their number of years together, she waited until Combs was out of town before packing up the house and taking everything – including the cars, the kitchen table and the nursery furniture for their youngsters – "because there was no other way. You think he would have let me walk out the door? He wouldn't have wanted me to go," she says.

"I wanted to be dramatic. I wanted him to know I wasn't breaking up with him for two weeks – or maybe leaving for two days. If I pack up everything – twins and all – it means I'm out! Puffy's an action person, not a talk person. So I had to have an action. Telling him, 'Babe, I'm leaving …' was not gonna do it."

As for why she ended the relationship, she says, after being asked about rumors that Combs fathered a child with another woman, "Hmmm ... Well, that definitely was part of it."

But, she also says, "I left because at this point in my life I want something different for myself. I invested 10 years, I have children, and I've always stood by him. But now it's time for me and what I want to do for Kim."

When contacted by PEOPLE, a rep for Diddy said: "We're not commenting."

Porter, 36, and Combs, 37, are parents to son Christian, 9, and twin daughters D'Lila Star and Jessie James, born Dec. 21. (Combs also has another son, Justin, 13, with stylist Misa Hylton-Brim; Porter has a teenage son, Quincy, with singer Al B. Sure.)

Asked if she'd marry Combs if he asked her, Porter replies, "I would say 'No.' And not because I don't want to get married, but because he's not ready to get married. When I get married, I want to stay married. I want both parties to be on the same page at the same time, and to leave a certain type of behavior behind. That's a commitment I don't think he's ready for."

Which is not to say the two are feuding. Over the Labor Day weekend, the former couple and their twins were playing together at his annual White Party in New York's East Hampton.

And, as Porter tells Essence.com: "You know how when two people go their separate ways, most of the time there's animosity? It's not like that with us. Sean and I have this bond, this friendship. It's not about 'if you're faithful to me, if I'm being faithful to you.' We're friends. I'm the person he can tell his inner most thoughts to, and he's that person for me. He still calls me everyday and we talk."

She adds, "There's no ill feeling or 'I can't stand you, I hate you, don't call.' There's none of that. We have three children together so that's just not an option. We're committed to our children even if we couldn't commit to each other."


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