PARTY monster Blake Shelton’s fed-up wife Miranda Lambert has walked out on him to go back on tour – just when they were finally set to spend two whole weeks together!

The two country superstars, who spend more time apart than to­gether, reunited to celebrate Blake’s 37th birthday on the June 18 fi­nale of “The Voice.”

They were also planning to spend some quality time together on their 1,200-acre ranch in Tishomingo, Okla.

But instead of taking “a couple weeks off,” as Blake said they planned, sources say Miranda left him at home and headed to Colo­rado and Montana to perform solo gigs when her group, the Pistol An­nies, canceled the June concerts.

“Blake said she didn’t have to do it, but she told him she didn’t want to let the fans down,” revealed a source.

 “Blake responded: ‘What about me?’ He was furious, but Miranda had already made up her mind.”

Then, the source says, fiery Miranda, 29, headed out on tour despite Blake’s wishes.

“Miranda is sick of Blake’s booz­ing and the reports of his womaniz­ing,” said the insider.

Blake boasted about getting stinking drunk after his singer Danielle Bradbery won Season 4 of “The Voice,” declaring “we are going to blow it out. That means drinking our face off.”

While he admits boozing, Blake denies cheating, but the source says: “Miranda has her doubts.”

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