Rob Kardashian credits Blac Chyna for getting him through his "darkest times".
The 29-year-old star had retreated from the public eye for two years as he battled depression and weight gain but says embarking on his romance with the 28-year-old model - who is pregnant with his first child - has changed his life for the better.
He said: "She got me through my darkest times. I wasn't happy in my own skin. I missed out on so many things.
"I've been friends with Chyna for a long time. She was someone I reached out to for advice. She would cook for me and we'd just talk. She's surrounded me with a lot of positivity. From the moment we met, I knew I wanted to be more than friends."
These days, the 'Rob & Chyna' star is happier than ever but admits he still has "dark days".
He told People magazine: "We just want to live our lives the way we want to.
"There were definitely dark days for me, and I'm still not fully happy looking at myself in the mirror. But I'm working towards that. And I'm happy."
Meanwhile, Chyna - who also has three-year-old son King Cairo with ex-partner Tyga - insists she has never set out to "change" her fiance, only to be a source of support.
She said: "I saw Rob was willing to better himself. "I had never wanted to be tough. I never wanted to change him."
Rob added: "Chyna definitely motivates me. Being with her got me over the insecurity of being out in public."
Chyna recently admitted she the secret of their eight-month relationship is that Rob "accepts" her "craziness".
She said: "I can do the craziest stuff or say the craziest stuff, and he doesn't judge me. Like if my stomach hurts, I don't have to pretend. I can go straight to the bathroom. It's those little things that really make a big difference."
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