Christina Aguilera Shares Rare Glimpse Into Life at Home With Fiancé Matthew Rutler

Christina Aguilera knows there ain't no other man for her.

The "Beautiful" singer opened up about her feelings for her fiancé, Matthew Rutler, in honor of his birthday on Monday, April 5. She gave a look into their private life at home in a mushy Instagram post, which included a video montage of their most romantic moments, set to the Schitt's Creek love song "Simply the Best."

Christina, 40, wrote, "You're simply the best, @m_rutler! Happy Birthday... You continuously impress me with how devoted, driven and hardworking you are, while being a devoted, loving and thoughtful parent & partner."

She continued, "You always strive to be better and never settle for anything but. From being an amazing father to an incredible business man and forward thinker, you innovate and execute ideas on the daily."

Xtina is mom to Max, 13, with ex-husband Jordan Bratman and Summer, 6, with Matthew.

Christina Aguilera's Best Looks

She not only praised her fiancé on his parenting skills, but also on his business acumen. According to his LinkedIn page, Matthew is an investor and Executive Vice President of MasterClass, the company that offers online lessons from Gordon Ramsay, Alicia Keys, Shonda Rhimes, Spike Lee, Natalie Portman, Jodie Foster and more celebs.

"I remember when Masterclass was just a little idea being tossed around our backyard," Christina wrote. "Now knowing and seeing first-hand the backstory in how you helped grow it to become the mega success it is, I'm not surprised because I witness the magic behind the machine every day — in every sense of what you do."

Her note ended with, "From helping keep the family glue together to building the successes you do. I'm proud of you and will always be in your corner...cheering you on to keep shining and succeeding in all your wildest dreams. Love you baby."

The former Voice judge, who divorced Jordan in 2011, got engaged to Matt on Valentine's Day in 2014.

Her birthday video for Matt included clips of their normal, at-home adventures: cuddling with their dog, crashing into toys, playing in the snow, kissing at dinner and surfing.

It concluded with a video of her and her kids in the yard at home. She shouted, "Happy birthday, Matt! We love you!" as they excitedly sprayed water on the lawn.

Matt showed her some love for V-Day this year, taking his wife-to-be on a helicopter date over the Pacific Ocean, white wine in hand. He wrote at the time, "What a ride it's been! And we're just getting started. You still make me crush. Every. Single. Day."

All that's missing from this love fest is Noah Reid and Dan Levy's reaction to Xtina using their love song from Schitt's Creek.