Miranda Lambert split from Evan Felker because he ''broke her rules''.

The 'House That Built Me' hitmaker decided to go separate ways from her boyfriend after six months together because he did something she didn't approve of.

A source told People magazine: ''I don't think it was a dramatic split, but he knew what he was 'allowed' to do based on her rules and he broke them. He did something that he knew she wasn't going to approve of, she assumed he did it and he didn't deny it.''

Miranda confirmed she and Evan had split up, describing herself as ''happily single''.

She shared: ''Love is a hard road sometimes and it's been a roller-coaster ride for me, but I'm definitely thankful for all the ups and downs because I've had some really good songs come out of it. You've got to take the bad parts and put them on paper and then move on to the happy parts.''

Meanwhile, the blonde beauty previously confessed she doesn't want to relive the ''hell'' of the last couple of years.

She explained: ''It was going to be hell, and I'd already been through hell. It was hell putting it on paper, putting my words on paper. So, I didn't want to rehash. I'd finally gotten to a place where I wasn't sad anymore. All the sad moments were there, all the truths were right in those songs. All you had to do was listen. I didn't need to say anything. When the music was out, people had listened, I got on the phone for the first interview. First question was, 'How do you feel about Gwen?' I hung up. I told [my manager], 'I just can't do this.' What was in the music was real, and I wanted people to get it from that. Take from it what they would. Then if I needed to talk, I would. But I haven't really. Until now.''