the odd perspective of the girlfriend

I was channel surfing the other night and came upon this movie many minutes after it had begun, so I missed any set-up between the professor and his girlfriend Sara. I had never seen the movie but was in the mood to put my brain in neutral for the evening, so I continued watching what inevitably for me became a very tired and boring film. But here's one element of it that *really* stood out in its oddness for me: Way into the movie, Weebo finally makes a same-scene appearance with Sara, and Sara was completely at ease and accepting of this floating, artificial intelligence robot, engaging it in conversation and knowing full well all along that it had been invented by her boyfriend professor. That shocked me. I wasn't aware Sara even knew of the robot's existence. (Remember, I came upon the movie late.) Why, then, was she so dismissive of the professor's new invention, "flubber"? She acted irritated and cynical whenever he tried to show its properties to her, and I was utterly confused how she couldn't accept flubber but was completely embracing of the robot. But, yeah, it was an awful movie anyway, filled with illogic, so maybe I've answered my own question.