Justin Bieber's 18th birthday bash must have been a memorable one and why not, he's 18 and he's rich. But most importantly he's in love with his gorgeous lady love Selena Gomez. "He was all over Selena the whole time, walking her around by the hand. He kept kissing her," an onlooker said. "It's clear she was the best part of the night for him. He is still so in love with her.