Johnny Depp and Amber Heard
Actor Johnny Depp and his fiancee, model Amber Heard, arrive at the Metropolitan Museum of Art Costume Institute Gala Benefit celebrating the opening of "Charles James: Beyond Fashion" in Upper Manhattan, New York, May 5, 2014. REUTERS/Lucas Jackson

Wedding plans are believed to already be in place for Johnny Depp and Amber Heard. However, sources claim the 28-year-old actress is having second thoughts in marrying the 51-year-old because of his behaviour.

Sources told US Weekly that Amber Heard is having doubts in marrying Depp allegedly because of his erratic behaviour and "mood swings." It reportedly annoys the actress thus she's contemplating backing out of the wedding.

"She's realizing she might be happier with someone else," the source said.

It's believed Amber was even unhappy with Johnny Depp's display during the Hollywood Film Awards presentation last month. The actor made headlines after he slurred his way through a speech. The actor was allegedly drunk during the event. The New York Daily News cited a Star Magazine source who claimed Amber couldn't believe that the actor "had made such a fool out of himself."

"This reflects really badly on her, and she's not happy about it," the source said, adding that his behaviour is "driving everyone away" including his fiancé.

In his 2013 interview with Rolling Stone magazine, Johnny Depp admitted he doesn't have the "physical need for alcohol." He described his love for wine and spirits as more of a "self-medication over the years just to calm the circus. " He had even admitted to have been sober for 18 months. However, he was speculated to have been drunk while presenting the Hollywood Documentary Award to "Supermensch: The Legend of Shep Gordon."

The Star Magazine source claimed "there's chatter in Johnny Depp's camp" about sending the actor to rehab. Even after getting engaged to Amber Heard, doubts crept in that the actress will ultimately be able to tame the actor's wild side. The source supposed Depp only "just stopped partying or is hiding his partying to be a good and upstanding guy for Amber."

However, Johnny Depp and Amber Heard have remained mum on these speculations regarding their wedding. Their reps have yet to comment as well on the reports. Regardless, they reportedly already have wedding plans in order. A source revealed to U.S. that the couple, who got engaged in 2013 after a year of dating, will have an intimate ceremony. It will only be close friends and family joining the nuptial, which is said to take place on Amber beach, the actor's Bahamas Island named after the actress.