"Shelton was back in the doghouse when Lambert allegedly caught him getting a little too close with 21-year-old supermodel Alena Shishkova on Twitter.
It went down Tuesday night at the ACM Honors in Nashville, TN.
Bentley immediately ran it up a tree and posted a picture on Twitter.
Said a source: "It ticked off Blake – first, that she gave Dierks a gift, and then that he had to post about it!
"And it is with heavy hearts that we move forward separately.
We are real people, with real lives, with real families, friends and colleagues.
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