Kenny Chesney is enjoying being a bachelor, but that doesn't mean marriage isn't on his mind.

"I thought I was ready once before, but I wasn't," the country star tells PEOPLE magazine, referring to his four-month marriage to actress Renée Zellweger in 2005. "If I get married again, I'm going to give it 150 percent."

Chesney calls his divorce a "life lesson." Still, he says it was devastating.

"There was nothing that made me happy," Chesney reflects. "You can't fall in love as hard and fast as we did and not have some residual effects."

Chesney and Zellweger have remained close friends. He calls his ex-wife "the sweetest soul I've ever met."