Justin Bieber is known for pouring his heart out in his music. His ex, Selena Gomez, has inspired a bunch of his songs over the years, but now that he's married to Hailey, the 25-year-old singer has a new muse. Bieber is releasing Changes - his first album in five years - on Valentine's Day, and he's made it clear in his Seasons YouTube documentary that it's basically a tribute to his wife. And if you've listened to "Yummy," you know he isn't holding anything back. Ahead of his album release, take a look at all the songs Bieber has penned about Hailey so far.