Nov. 7 should have been a great day for Lamar Odom. But when he celebrated his 38th birthday at Sista Mary's Soul Food restaurant in Glendale, CA, the former NBA player “seemed really sad,” an eyewitness tells In Touch exclusively.

There were about 30 guests at the bash, “but everyone seemed like strangers to Lamar, except for a handful of people,” adds the eyewitness, noting that Lamar, who sipped a cup of tea with honey, looked especially solemn when a poet named ElectraBe performed a tribute to him. “It was a very serious and personal poem,” says the eyewitness. Instead of celebrating Lamar's life, the poet touched on some very dark topics like Lamar's drug addictions, the untimely death of his mom, his 2015 near-fatal overdose in a Nevada brothel and losing his 33-year-old former wife Khloé Kardashian, who is now expecting her first child with basketball player Tristan Thompson, 26.

lamar odom and khloe kardashian - getty

After the poet was done, “Lamar got up and went outside — you could tell the poem made him sad,” says the eyewitness, adding that everyone was in shock. “Nobody wants to be reminded that they’ve had a messed up life [on their] birthday!”

This comes after the basketballer collapsed in a VIP booth at an LA nightclub in the early morning hours of Sunday, Nov. 5. A source close to Lamar spoke to People magazine about 38-year-old's current state. “Lamar is spiraling again. He’s out of control," the source said. “He was better this spring but things got worse over the summer and everyone is worried things are going to get even worse and they’re scared for him.”

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