The 20-year-old makes her comments in an interview with the November issue of Glamour magazine.
Talking about the 18-year-old actor, who she was rumoured to have dated, the country singer said: “He's one of my best friends.
'He's wonderful, and we'll always be close. I'm so thankful for that.'
The Grammy Award winner also spoke about being 'stoked' about meeting Sir Paul McCartney, who she was due to meet at a concert in Nashville.
She said: 'When I found out I was going to get to meet him, I couldn't talk – I was so stoked.
'I'm bringing my whole band with me; they are geeking out!'
The singer also told the magazine that she keeps herself grounded by not reading anything that is written about her in the press.
She said: 'Recently, I stopped reading articles about myself. Even if it's not bad, I think actively caring about people's daily perception of you makes you second-guess everything.”
She added: 'I am very happily not paranoid right now.'