Ashley Monroe penned all of the songs on her 2013 Like a Rose album, but she admits that she has trouble writing sometimes -- specifically, happy songs.

"It's so hard for me to write a positive song, but there are so many that I love that actually have some meat and substance to them," she tells Billboard. "I really wanted to challenge myself [for my new single]. I tried to think of some Sheryl Crow songs I love that are uptempo and make you feel good. I love those songs, I've just never written one."

Monroe co-wrote her current single, "On to Something Good," with Luke Laird and Barry Dean, and she says that it carries a valuable message, for herself as well as her fans.

"I really think it's important to express hope to people -- and to myself -- that if you're alive and breathing, you're doing so for a reason, even if you've been through hell in the past," the singer adds. "I think it's a way to say, 'Keep going' ... Just live. Don't overanalyze. Just go with it."

Perhaps Monroe's recent good luck helped her get in the right mindset to write a happy tune. She wed professional baseball player John Danks in 2013, and her collaboration with Blake Shelton, "Lonely Tonight," has become a big hit.

“As cheesy as this might sound, that’s exactly how it felt,” she says. “I like that the song is hopeful, and it’s saying, ‘Hey, we’ve all been there. We all know what it’s like to be down and out, but there’s hope if you keep on going. And if you do, you will be on to something good.’”

Still, Monroe acknowledges that some of her best songs come from when she is facing difficulties.

"When I'm happy, I'm not inspired to write about it as much. I'll go to the park, for a walk, or simply go be happy," she explains. "But it's in my dark moments that I feel the heavy heart that I want to write about."

Download "On to Something Good" on iTunes.

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