Heche and Laffoon went through a messy two-year divorce that was only finalized in March.
The pair shares a son, 6-year-old Homer, and Heche pays Laffoon child support for him.
And the star made it obvious that their split has been anything but amicable while chatting on The Late Show with David Letterman on Wednesday.
When quizzed by Letterman about what she thought of her former husband, Heche joked, "Can you say 'lazy a**' on TV?"
And she didn't stop there, explaining to the amused audience about how Laffoon makes a living: "He goes out to the mailbox and he opens up the little mailbox door and goes, 'Oh! I got a check from Anne! Oh! I got a check from Anne! Yay!'"
The star then mocked her ex for his dreams of becoming a soccer coach -- and for repeatedly inviting her to watch his games.
She added, "I think he wants to coach soccer right about now. It's funny because you can't quite let go of the ex.
"He wants me to come and watch him run around in his little white shorts playing soccer. Honestly, I don't want to come to rehearsal and watch you run around in your tight shorts like trying to pretend you know how to play soccer. I divorced you! I don't want to hang around with you Thursdays and Saturdays and maybe on Sunday."
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