The 'Firework' hitmaker – who broke up with the actor on December 30, 2011 when he filed for divorce - took to her twitter account after a two-week break to pay tribute to her supporters and reassure them she has a "happy heart" again.
She tweeted yesterday (08.01.12): "I am so grateful for all the love and support I've had from people around the world. You guys have made my heart happy again."
The pop star – whose last twitter entry was on December 27 – also insisted she is the only person who speaks for herself after her evangelical mother and father spoke about the split last week.
She tweeted: "Concerning the gossip, I want to be clear that NO ONE speaks for me. Not a blog, magazine, "close sources" or my family."
Last week, Katy's parents Christian pastors Keith and Mary Hudson spoke about the pair's break up for the first time from the pulpit of their church.
Mary said: "I'm sure that Katy's trending on the Internet was to get you here to church tonight.
"I mean all over the world, who knows how God is bringing them in? The most important thing is you are here and God wants to put the fire in you in 2012."
Since filing for divorce, Russell has been residing in the UK, while Katy has been staying with her grandmother in Santa Barbara.