"It's hard to find the words here...but I feel extremely grateful for the years of marriage to Morgan 

The "Heartfirst" singer, 28, filed for divorce from the "Kiss Somebody" musician, 37, on Friday

after nearly five years of marriage, court documents obtained by PEOPLE show.

"They've been working on their marriage for a very long time.

Prior to this they had separated privately once before and have been in therapy for several years," a source tells PEOPLE. 

"They gave it their best go but unfortunately arrived at the decision to formally separate."

This is now public record so I wanted you to hear from me directly that I am going through a divorce.

In April, Ballerini again touted the benefits of therapy to Extra, saying that she and Evans go both separately and together.

"I think it's really important," she said. "Obviously we have a strange life.

Like, we are both really busy and don't get to spend as much time together… And just trying to find, like, the things that work for us."