I want my partner to disregard her family
Does she normally disregard her family for any reason?
Yes she does because every time I see her I'm sure she's at home causing drama about serious family matters.
I think that you should make sure that is what she really wants. It is not okay to tell her to distance herself even more from her family.
Her family causes her more trouble than they are worth. They also ignore her.
Well having a conversation with her about this sounds like the best option to take. Telling her to ignore her family is simply a very unrealistic request to say the least.