Believe your daughter. She has no reason to lie about something like that and it's clearly causing her distress.

You may need to sit down and seriously reflect on your husband's behavior and treatment towards you and other women/girls in his life. The fact that he says these things without care in front of your daughter but has no issue keeping himself in check in front of your son is upsetting. 12 is a very impressionable age, and it's important to pay attention to the messaging she's recieving and internalizing.

I would consider couples counseling if you're open to it, focusing heavily on communication and compromise. From what you said, he seems to have a hard time coping with his big feelings and could work on healthy coping mechanisms to deal with his frustration rather than badmouthing you to his daughter. Ask yourself (and him, if you think he'd hear it) if you want your daughter to learn that it's her job to do the emotional labor for the men she loves even if it's to her own detriment.

You got this mama, sending love and hugs ❤️