Just three weeks after the birth of his first child, a baby girl named Ava, Backstreet Boys singer AJ McLean has revealed exclusively to In Touch that he has fallen off the wagon in his lifelong battle with alcoholism.

“A few weeks ago I had a really bad day, I was in a funk,” the 34-year-old pop star confesses to In Touch. “I went out in Hollywood and had a couple of beers and maybe one or two shots.”

But the singer admits that this lapse in his willpower has happened several times in the past year.

PHOTO: Meet AJ McLean's Baby Girl Ava

“This happened two weeks ago, roughly,” he says. “Before that, I was sober for almost a month. Before then, four months. It’s been sporadic.”

The star has famously battled with alcohol and drug addiction for more than a decade and has entered rehab three times (2001, 2002 and 2011) in attempts to beat the problem.

“I will forever be an alcoholic and an addict in recovery as long as I live,” he tells In Touch. “It’s an ongoing struggle, a daily thing.”

And now that AJ is a father, making a solo record and working on a jewelry line, he admits he’s “trying to be a good husband and a good father and deal with life on life’s terms,” adding, “There is a lot going on. It’s been overwhelming.”

GALLERY: AJ Shows Off His Backstreet Girl

AJ and his wife of one year, Rochelle, welcomed their daughter on Nov. 27 and it’s Ava who he knows will bring him through this dark time.

“I can’t stress how much my daughter is an inspiration to stay sober,” the star says. “When I come home and she opens those big blue eyes at me, it’s the most amazing feeling I could ever feel. I’m not looking for sympathy. It’s a constant struggle, and it’s not as easy as you think.”

For more on AJ's new life as a dad and his struggle with sobriety, pick up next week's issue of In Touch.

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