Subverted: Another character comments on their crazy relationship, only for Maria to insist "He's not my boyfriend."
They hook up in the end anyway.
He's her project/apprentice/slave thingy.
Parodied: Maria uses every perceived slight to bring Lenny down a notch, despite the fact that the two of them are actually fairly equal, all things considered. Lenny decides it's easier to just go with it.
Deconstructed: Maria sticks with Lenny to boost her own ego, knowing that she's far better than him and can hold that over his head. Lenny eventually cracks under the pressure of trying to keep her favor, and they break up (much to her shock; how DARE something like him break up with HER?!)
Played For Drama: Maria is the one good thing Lenny has going for him, and she's fully aware of it, so she constantly derides and insults him but in doing so, she's unintentionally wearing away the good parts of their relationship. All the while, Jason is watching and plotting to steal her away — not out of love, but 'cause she's hot and it would cause Lenny even more pain.