"Like a teenage boy just absolutely lovestruck," the source said. "He would have done anything for her, and that was a little red flag for some of his friends."
The insider added, "Like, he was crazy in love with her, crazy being the keyword."
Bourdain and estranged wife Ottavia Busia split in 2016, but their divorce has not been finalized. Because of that, Busia is legally Bourdain's next of kin. The couple share one child, 11-year-old daughter Ariane.
While his love for Argento was clear, the source noted that the depths of Bourdain's pain struggle were not apparent.
"That being said, none in our circle of friends knew he was struggling in any life-or-death way," they said. "Honestly, I don't think anyone knew. I don't think Eric [Ripert] knew the depths of his pain. The shock of Tony's death is almost as profound as the pain."
The source continued, "Even his closest friends are still waiting for some mystery to be uncovered. We knew his nerves were shattered a little; his marriage had fallen apart, he was way, way overworked and overdriven, but unstable… No one had a clue."
Bourdain was found in his hotel room in France on Friday by his friend and fellow chef Eric Ripert while filming an episode of Parts Unknown in the country. His death was announced in a statement by CNN.
"It is with extraordinary sadness we can confirm the death of our friend and colleague, Anthony Bourdain," the statement read. "His love of great adventure, new friends, fine food and drink and the remarkable stories of the world made him a unique storyteller. His talents never ceased to amaze us and we will miss him very much. Our thoughts and prayers are with his daughter and family at this incredibly difficult time."
In a tweet, Ripert expressed his sorrow alongside a photo of himself with Bourdain.0comments
"Anthony was my best friend. An exceptional human being, so inspiring & generous," he wrote. "One of the great storytellers who connected w so many. I pray he is at peace from the bottom of my heart. My love & prayers are also w his family, friends and loved ones."
Photo Credit: Parts Unknown / CNN