Mel Gibson's Step-Mom -- Mel Better Pay for My Divorce

Mel Gibson's step-mother insists it's all Mel's fault she's getting divorced from the actor's father -- and now, she wants Mel to pay her legal bills.

Teddy Joye Hicks Gibson just filed legal docs in L.A. County Superior Court, asking a judge to make Mel a party in her divorce proceedings with Mel's father Hutton Gibson, who filed for divorce back in June.

According to the docs, filed by attorney Brian J. Kramer, Mel not only pushed his father to divorce Teddy -- he booted her from her marital home too ... and has been covering Hutton's legal bills.

As a result of his alleged involvement, Teddy wants a judge to order Mel to pay HER legal costs too -- which she estimates will be around $65,000. She says she has already spent $30,000.

Teddy also wants a judge to order Mel to let her back into her house. (As we reported, Teddy is already seeking a restraining order to block Mel from kicking her out, but that hasn't been ruled on yet).

And there's more ... Teddy wants $15,000/month in spousal support from Hutton -- an expense Mel would probably be footing.

There's a hearing today to rule on Teddy's latest request.