SELENA GOMEZ celebrated her Nylon magazine cover with a party Tuesday night in West Hollywood. The newly single star had a private dinner at Soho House and her closest friends were in attendance (hint: Justin Bieber did not make the guest list)."She was so happy,” a source at the party tells omg!. "It was a total girls night, and she was hanging out with her parents and close friends.”Those friends at the Coach sponsored dinner included her "Spring Breakers” co-star Ashley Benson, plus famous pals Ashley Tisdale and Jaime King.Yesterday was no doubt an eventful day overall for the actress. Ex-boyfriend Bieber, 18, dropped his "Believe Acoustic” album Tuesday and featured on was it the song "Nothing Like Us,” in which he confessed about his breakup with Gomez, 20.Aside from one jab about Selena Gomez’s "drinking,” Bieber, 18, seemed incredibly sad on the ballad."There was no talk of Justin last night,” adds omg!’s source. "It was all about a girls night.”Agencies