Jane departed Walford in January after accepting a new job in Cardiff, while in real life, Brett has just signed up for a new regular part in Waterloo Road.
The actress is also competing on the current series of Let's Dance for Sports Relief, recently appearing as Lady GaGa for a rendition of 'Telephone' on the show.
Speaking to the Daily Record about her EastEnders career, Brett insisted that it was the right time to say goodbye to Jane for the time being.
Brett commented: "It was time to leave. I loved playing Jane. I left when she still had a lot to give, but it was the right time to give her a break at least, because I think she's gone round in circles."
"I wanted to try something new," she added. "I just didn't think that would be pretending to be Lady GaGa, but there you go!"
The Scottish star has also said that she is "really excited" about working in her native accent for Waterloo Road when she begins filming next month.
> Laurie Brett, Tameka Empson, Terry Alderton in Let's Dance final
> Read more EastEnders news and spoilers
Watch Jane's EastEnders character trail in the video below: