Maybe not(and he knows it, you could see he wanted none of that fight and left with a "nice hook Marty"), but that was a total asshole move by Maggie. She shows up, takes in the scene, which is to say she knows Rust has completely jumped off the wagon and generally has accelerated on his downward spiral and... well I'm just here to do what I came here to do and fuck whatever it's gonna cost this guy. Whatever pity she had after that first dinner when Rust told her about his kid is long gone, she's been blasting this poor guy for like 3 episodes straight.