James Bay Gives Fan an Inside Look at Life with Partner Lucy Smith in 'One Life' Music Video — Watch!

James Bay's only got "One Life" ... and he wants his girlfriend there for all of it.

Thursday marked the release of Bay's music video for his sweet new track "One Life" which details the journey between a couple falling in love, to getting pregnant and raising a baby together. The song itself, however, is inspired by Bay's very own relationship which he's largely kept under the spotlight — until now.

"Lucy and I have been together since we were kids growing up in the same home town," Bay, 31, tells PEOPLE of his girlfriend Lucy Smith, with whom he shares his 20-month-old daughter Ada Violet. "She has been such a huge part of my journey. We've known each other since before I even started to perform as a solo artist."

James Bay James Bay and Lucy Smith

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He continued, "For the last 10 years, keeping our private life private has always been very important to us. But it also got to a point where I didn't want to carry on acting as if Lucy doesn't exist. This song is a celebration of our journey so far and felt like the perfect way to express that."

The "Move Together" singer also says that he got a good reaction from Lucy when he showed her the song and music video — and he really values her opinion.

"Lucy is one of my greatest judges and best critics. I really need that from her and wouldn't want it any other way," he says. "It wouldn't work if she just told me she loved everything I write. That being the case, I really feel like I've got something if I write a song that she wants to listen to on repeat. One Life was one of those songs and I'm really proud to say so!"

Ahead of the song's release, Bay teased it on social media and wrote that "One Life" is a song he wrote about "the most precious and private part of my life."

"I've never been great at sharing my private life on here. I'm ok with that. But I'm learning that sometimes it's ok if the lines blur. All that said, music making (and listening) is such a personal experience and you guys are amazing at sharing your experience of that with me," he captioned the Instagram video which included a series of photos of the couple together through the years.

"One Life is a song I wrote about the most precious and private part of my life, my relationship with Lucy. I didn't know if I'd be able to sum it all up in one song, I'm still not sure I ever will, but this one feels like it got close."

He concluded, "It's about the realisation that for all the somethings I chase after, it's actually just a someone that I really need. Lucy has been next to me every step of the way, I feel extremely lucky that I get to say that."

Julian Broad James Bay

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He later shared the same video on TikTok, and expanded more in the caption section writing, "I didn't know if I'd be able to sum it all up in one song, I'm still not sure I ever will, but this one feels like it got close."

"One Day" comes ahead of the release of Bay's forthcoming album Leap, set for release in July — and is expected to be his most personal album to date.

"In 2019 I was really struggling. I started writing songs to try and help me deal with fear, anxiety and problems with self-confidence. Feelings that run deep, that I've never wanted to share. Somehow, it all turned into some of the most hopeful and uplifting music I have ever made," the singer-songwriter said in a press release about Leap.

He added, "I spend a lot of time (too much time) tangled up in negative thoughts. It's so easy to spiral. But during all that extra time writing, I decided to embrace my sadness rather than fight it and I began to recognize what lifts me up when things get tough."

Leap is out July 8.