Rihanna. Picture: Instagram

Rihanna thinks people set unrealistic expectations for their partners.

The 30-year-old singer has admitted she has a lot of friends who come to her with "boy-advice questions", and she often has to tell them to "be fine" with the type of person they are dating, rather than expecting them to change into someone they're not.

Speaking to Britain's Vogue magazine, the 'Wild Thoughts' singer said: "I think a lot of people meet people and then they're dating the idea of what the person could become, and that person never shows up and then they're just mad disappointed. A person can always get better, they can always get worse, but you've got to be fine with what you met them as."

Rihanna has been all about giving advice and support to her friends lately, as last month her 'Ocean's 8' co-star Anne Hathaway revealed the 'Work' hitmaker had heaped praise on how good her butt looked.

Anne returned to work for the first time after giving birth to her son Jonathan, now two, for the movie, and was nervous about what her co-stars - including Rihanna, as well as Cate Blanchett and Sandra Bullock - would think of her.

In June, she said: "I walked on the set, and, you know, my weight's a little up and I'm just aware of it. And I walk on the set and I'm my jeans, and I've done my best and I'm going to love myself no matter what.

"And Sandy Bullock looks up and goes, 'Looking good, mama!' And it made me feel amazing! Cate Blanchett's like, 'Nice jeans, Hathaway!' 

"And then Rihanna looks up and goes, 'Damn girl, you got an ass!' And I of course freaked out and loved it so much. I was like, 'Really?!' And she goes, 'You got an ass like me!'"