Melissa and Tammy 'just drifted apart'

A source has said that the split between Melissa and Tammy Etheridge was amicable.

The couple, who announced their break-up earlier this week, apparently separated five months ago. A friend told People that there were no bad feelings at the end of their nearly nine-year relationship.

"There’s no third party involved," the source said. "They just drifted apart over time. There's no animosity whatsoever – they are on friendly terms."

The couple are parents to twin girls Miller and Johnnie Rose, 3.

Melissa, who is also the mother of two children from a previous relationship, will reportedly continue to co-parent while she tours in support of her newest album Fearless Love, due out April 27.