Gwen Stefani Gavin Rossdale
"Used To Love You" singer Gwen Stefani flirted with NBC "Voice" coach Blake Shelton on Twitter on Monday. She is pictured above with her estranged husband, Gavin Rossdale, Sept. 5, 2014. Getty Images

No Doubt singer Gwen Stefani sent a shout-out to fellow NBC “Voice” coach Blake Shelton on Monday amid rumors that they were dating. The two have both denied they were in a relationship, but continue to flirt on the hit reality singing show.

Stefani, 45, posted a photo of her and the country singer to Twitter on Monday. "Hi @blakeshelton @NBCTheVoice gx,” she captioned the image to her 2.18 million followers. The post was liked 1,400 times and got dozens of shares.

The “Just A Girl” star is thrilled that her divorce to ex Gavin Rossdale, the singer of Bush, is going so smoothly. “It was heartbreaking and is still heartbreaking going through this whole process, but the fact that Gavin has been very adult in settling everything between the two and really been a man about it has been very therapeutic for Gwen’s healing,” an insider told Hollywood Life in an exclusive report Monday. “She looks at this easy divorce with little drama being the best possible scenario to finally move on with her life.”

The star released a new ballad, “Used to Love You,” where she sings about her split: “I thought I was the best thing that ever happened to you/I thought you loved me the most/I don’t know why I cry/But I think it’s cause I remembered for the first time/Since I hated you/That I used to love you.”

The duo agreed to joint custody of their three children, Kingston, 9, Zuma, 6, and Apollo, 1. “There are no issues when it comes to custody,” a source told People earlier this month. “Gwen and Gavin both agree that the boys should be able to spend as much time as they want with both of their parents.”

There are some reports that claim their financial settlement was amicable, but Radar Online wrote Monday that he tried to -- and won -- her millions. Stefani “agreed to give Gavin half of her net worth,” an insider told Radar Online on Monday. “In addition, Gavin was able to keep his own fortune. That wasn’t even on the table as part of the settlement. So Gavin is now wealthier than Gwen, despite the fact that she is much more successful than he is in the professional world!”

The couple started dating in 1995, but announced their split in August after 13 years of marriage. “While the two of us have come to the mutual decision that we will no longer be partners in marriage, we remain partners in parenthood and are committed to jointly raising our three sons in a happy and healthy environment," they said in a statement via E! Online.

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