Kate Gosselin isn't paying her "bitter haters" any mind amid her son Collin's abuse allegations ... in fact, she says she's happy.

The "Jon & Kate Plus 8" star responded to a supporter on TikTok who told her mothers are blamed for everything and to protect her mental health, with Kate saying ... "Thank you. Yes I totally agree."

She continued ... "I was 'guilty' when I was silent and now that I'm responding, I guess I'm saying too much that is true and that makes sense so now they say I'm 'guilty' for answering."

Kate also clapped back at critics in her reply, adding ... "What a bunch of bitter haters! I AM happy and nothing they can say can change that!"

As you know, Collin's lobbed various abuse allegations at the Gosselin matriarch, claiming she allegedly once zip-tied his hands and feet.

Kate fired back, implying that her son is mentally ill and denying his allegations against her.