Lambert and Shelton have maintained a friendly relationship since their divorce

By Katherine Foreman
Updated August 19, 2015 01:30 PM
Credit: Kevin Mazur/WireImage

It’s been nearly a month since Miranda Lambert and Blake Shelton announced their divorce and through all the speculation and rumors surrounding the split, the couple has kept things friendly.

The “Heart Like Mine” singer was spotted Monday night at Whiskey Jam – a no-cost local showcase held each week at Nashville’s intimate live music venue Winners Bar and Grill – where she sat among the crowd supporting her fellow singer/songwriters.

When local songwriter Ryan Hurd took the stage to perform “Lonely Tonight,” a song he co-wrote with Brent Anderson for Shelton in 2014, Lambert was seen singing along to the popular hit, which also features her close gal pal Ashley Monroe.

“She was just at a table watching the artists with the rest of the crowd,” onlooker Jeremy Wist tells PEOPLE. “She seemed really happy and like her usual self.”

Lambert has had a lot to keep her busy throughout the past month, between her current tour, pop-up fundraisers, and girls nights out. The star Tweeted early Monday morning about an upcoming trip to Luckenbach, Texas, to promote her eighth Cause for Paws-Back to Basics event through her MuttNation Foundation, which raises money for animals in need.

She will be making an appearance at the charity event, set to take place on Sept. 18 and 19.

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