Sean ‘Diddy’ Combs shared a heartfelt tribute on social media to Kim Porter, his former girlfriend and mother of four of his six children, on Sunday.

Porter was found dead in her Toluca Lake, California home on Thursday. There has been no information on the cause of death, but the supermodel reportedly had flulike symptoms and, possibly, pneumonia for weeks.

“For the last three days I’ve been trying to wake up out of this nightmare. But I haven’t,” Combs wrote on Instagram. “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.”

Combs and Porter were an on-and-off couple for more than a decade and remained amicable after officially splitting in 2007. They had a son, Christian, 20; and twin daughters, Jessie James and D’Lila, 12.

The Combs family was often revered for how well they have blended their children from previous relationships. All of their kids were raised together including Diddy’s adopted son Quincy, 27, Porter’s son with singer Al B. Sure!; Justin, 24, Diddy’s son with stylist Misa Hylton Brim; and  Chance, 12, Combs’ daughter with Sarah Chapman.

The video clip showed the rap mogul and a then-pregnant Porter posing for an ESSENCE photo shoot in 1996. The sweet moment was set to R&B group SWV’s 1997 song “When U Cry.”

The former couple expressed the joys of depicting “Black Love.”

“We were more than best friends, we were more than soulmates. WE WERE SOME OTHER S**T!! And I miss you so much. Super Black Love,” the post concluded.

The Bad Boy Records founder also uploaded a series of photos with captions stating his grief over the sudden loss.

In a clip of their family, Combs promised to care for their offspring the way Porter would have wanted.

“I’ll raise our family just like you taught me to,” Diddy wrote. “Love you forever!!!! [Black heart emoji] I CANT BELIEVE THIS S**T!!!!!!”