Jonas hosted a Birchbox Men and Movember Foundation dinner at Chateau Marmont.
"He was in a good mood," an eyewitness tells me, adding, "He was so happy to see his brother [Nick] and be around his friends for the night. He was surrounded by his best friends."
Sources confirmed to E! News earlier today that Jonas and Hadid decided to go their separate ways because their busy careers were getting in the way of the romance.