Amber Heard and her artist/photographer girlfriend, Tasya van Ree, have reportedly broken up amid a swirl of rumors that the actress is dating actor Johnny Depp.

Heard and van Ree had been dating for four years, according to the New York Daily News. Last December, Heard first publicly came out as a lesbian at the GLAAD 25th anniversary celebration, which she attended with van Ree.

I think when I became aware of my role in the media, I had to ask myself an important question: 'Am I part of the problem?' she told the gay pop culture website, And I think that when millions and millions of hard-working, tax-paying Americans are denied their rights and denied their equality you have to ask yourself what are the factors that are an epidemic problem, and that's what this is.

Heard attended the event with her then-girlfriend, photographer Tasya van Ree, whom she had been dating since 2008.

She's so beautiful. I mean, you'd have to be crazy not to want to go out with her! Heard told

In Touch reported that the actress and her girlfriend quietly broke up months ago. The duo supposedly remain friends, and van Ree has been spotted enjoying the single life. [Tasya] was chatting and laughing with several beautiful women, an eyewitness, who recently spotted her at LA's Bar Marmont, tells In Touch.

If rumors are to be believed, Heard has been having her fun as well.

Just recently, headlines began to link Heard and Depp, with whom she co-starred in October's Rum Diary. A source told, He's smitten by her. They started sleeping together during the (Rum Diary) press tour.

Heard has reportedly been a regular visitor on the set of Depp's The Lone Ranger in New Mexico, according to the Daily Mail. Depp even reportedly gifted the beautiful 26-year-old with a horse, so she can join him on rides, according to E! News. In April, Heard was photographed boarding Depp's private plane bound for Las Vegas. Depp was there to promote Dark Shadows. People magazine reported that Ree was with Heard on the trip.

The actor officially split from Vanessa Paradis, his partner of 14 years and the mother of his two children, Lily-Rose and Jack.

Another source told Hilton that the 49-year-old actor and Paradis had an argument over Heard. Paradis was reportedly overheard yelling, If I see her, I'll drown her!

The actor has vocalized affection for the actress in the past. When I first saw Amber, it was like seeing an old-time movie star, Depp told USA Today in October. It was like I was seeing Lauren Bacall.

For her part, Heard has not been coy about her affections, either.

I'm making a movie with Johnny Depp. He's a beautiful specimen of a human being, Heard told USA Today while filming on the picturesque set in Puerto Rico in October. It was a wildly, wildly seductive combination. That moment quite possibly has ruined every other job for me.

She went on to tell Dazed magazine more about Depp, saying: He's such a wonderful presence; he is enigmatic and compelling and a true artist, seriously intelligent and incredibly sensitive. Everybody on set respects and likes him, which says a lot about an actor. It's a grueling job at times and the stress level that everybody feels in the industry is intense -- but it doesn't affect Johnny. It seems like he has time to look everybody in the eye, and I like that; it was wonderful to see.