Sean 'Diddy' Combs Too Upset to Speak at Kim Porter's Funeral Where Faith Evans Will Perform

Sean "Diddy" Combs is still mourning the death his ex-girlfriend Kim Porter as her funeral approaches.

Combs, who shares four children with Porter, was reportedly hoping to deliver a eulogy at Porter's funeral in Columbus, Georgia on Saturday, but sources close to him told TMZ that he may be too distraught to do so.

The 49-year-old rapper has reportedly been taking news of the model and actress' death especially hard, with sources having previously stated that he was "devastated" and heartbroken.

"This is the most awful, sad and unreal situation for him. It's a nightmare," a source told PEOPLE after news of Porter's death broke. "He is very much struggling. He isn't sleeping. He always had a very special relationship with Kim. Despite not being together romantically, he loved Kim. It was really true love and he is hurting badly right now."

Combs and Porter had dated on and off from the '90s through 2007, the couple having three children together – 20-year-old son Christian and 11-year-old twins D'Lila Star and Jessie James. Combs also acted as a father to Porter's son Quincy from a previous relationship.

Porter, 47, was found unresponsive at her San Fernando Valley home on Nov. 15. A 911 call had been placed, stating that Porter was in cardiac arrest. Upon the arrival of emergency personnel, she was pronounced dead at 11:40 a.m.

At the time of her death, authorities stated that the cause of her death was undetermined, adding that no illegal substances were found at her home. A source later claimed that Porter had been battling pneumonia.

On Nov. 20, Porter's death certificate was released following the completion of an autopsy.

"On Nov. 16, an autopsy was performed on Porter. The cause of death was deferred pending additional tests. Porter's body has since been released from our facility," a spokesperson for the Los Angeles County Medical Examiner-Coroner said in a statement.

The 47-year-old's death certificate listed her cause of death as "deferred" and the manner of death as "pending investigation."

Porter, who had a cameo in Diddy's 2008 reality series I Want To Work For Diddy, is set to be laid to rest in Columbus, Georgia this weekend, a service that will be attended by singer and songwriter Faith Evans, who is set to perform during the service, and Mary J. Blige. Porter's casket will reportedly arrive to the funeral in a horse-drawn carriage, an arrangement made by Combs to honor her love of horses.