Miranda Lambert
"Over You" singer Miranda Lambert, pictured June 27, 2015, was a "tinged hurt" to find out her ex-husband, Blake Shelton, was dating his NBC "Voice" co-star Gwen Stefani, a source said. Getty Images

“Over You” singer Miranda Lambert is bothered her ex-husband, country star Blake Shelton, is dating his NBC “Voice” co-star Gwen Stefani, People magazine reported Thursday. While Lambert agreed to their divorce in July, Shelton’s rebound relationship still stung.

Stefani, 46, and Shelton, 39, made their relationship official Nov. 4, the same day as the 2015 CMA Awards in Nashville, Tennessee. There was "a tinge of hurt when Miranda heard the news," a source told People. "But they are divorced, after all, and she wishes nothing but the best for Blake."

Lambert’s main concern isn’t who her ex is dating, though. She’s spending time with those closest to her and penning new songs. "Her concentration is on her new music, dogs, horses, life in Nashville and her family and friends," the insider said. "The simpler things in life."

If the right man comes knocking on the country singer’s door, she just might let him in. Lambert, 32, is "not concentrating on dating right now, but wouldn't rule it out.”

Even before they announced their relationship was official, Shelton and Stefani were plagued with rumors. The most recent gossip claims the “Used To Love You” singer is pregnant with Shelton’s baby.

The Oklahoma native denied the pregnancy with jokes and insults on Twitter Thursday. “Surely not...People can't be that dumb?” he said about the story, originally ran by OK! magazine Wednesday. “Damn I'm fertile!!” he wrote when one Twitter user said he was pregnant with Shelton’s baby.

When a different netizen said Shelton “used to be a good person,” he responded: “Ohh... So you read that bulls--- I was just talking about huh? Well.. [sic] Good luck!!!”

Stefani has not responded to the pregnancy drama, but it was rumored that she conceived her youngest son, Apollo, 1, while ex-husband Gavin Rossdale, Bush frontman, was allegedly having an affair with their children’s nanny.

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