People (Sept. 21st 2015)

Gwen Stefani Opens Up About Her New Music and Turning 46: 'I Feel Very Blessed to Be Alive Still!'

After a summer of big change for Gwen Stefani, the singer is focusing on her new music and looking forward to celebrating her birthday with her three boys.

The Voice coach – who announced that she and husband Gavin Rossdale were splitting in August – began writing songs for her upcoming album in June.

“[It’s] just truth,” says Stefani about an overall theme for her new music. “Just being clear and being true to myself. I just want to be fulfilled. It’s really quite selfish.”

Stefani has written 14 songs thus far, and “it’s like getting pregnant with 14 babies all at once,” she tells PEOPLE. “Every song that is added to the batch makes it different. Every single time I write a song, I think it’s my single and it’s very dramatic and everyone’s like ‘Okay, Gwen. Shut up. We know it’s not the one, but I’m glad you’re excited.’ ”

The singer – who’s partnering up with MasterCard for a concert in New York City on Oct. 17 – has been sharing her new songs with her loved ones (like her dad!) and even rocking out to them by herself. “My favorite is just weirdly listening to it myself in my car really loud at night,” says Stefani, laughing.

It’s not all work for the mom-of-three, though. Celebrating her 46th birthday next month, the star is just hoping to have a low-key day with her sons Kingston, 9, Zuma, 7, and Apollo, 18 months.

“I hate birthdays, although I feel very blessed to be alive still,” she says. “It’s been a really, really amazing journey. You can’t ever picture what it’s going to be like and there’s so many great things ahead, you know what I mean? I feel so grateful.”

So what does someone who isn’t the biggest fan of birthdays do on her big day?

“I heard The Sound of Music is playing live in L.A.,” says Stefani. “I might take the boys to that, and then probably some kind of Mexican food.”