In the beginning when she was staring at her through the window and when she was filming her, was the way those scenes were shot and acted just a red herring before the real reveal of who she was in love with?
shareShe was more in awe of her I think. Lisa was someone she wanted to be like.
shareI'm pretty sure it was meant to be a red herring to keep the mystery going longer.
I think the stare may have been her recognizing Lisa as her opportunity to manipulate events to get closer Matt. She hooked up with his best friend for the same reason. It may have been a little overdone in Lisa's case because when you realize she is not at all in love with her, you start getting suspicious about why you've been so obviously set up. You don't get that as strongly from her weird relationship with Luke... maybe because he's a slightly odd character so you kind of understand why she'd pull back.
Didn't she make friends with Lisa BEFORE Matt even met her? Lisa was breaking up with some other boyfriend, when she went to Alex's over the ledge. Then Alex made a video of Lisa which Mat saw and then followed Lisa, etc.
shareAlex had oily hair and no fashion sense when she first saw Lisa through the windows. I think they wanted to portray her as an undesirable and lonely person who longed to be admired by others, hence her wish to become an actress. Lisa was everything she wanted to be, so she secretly observed her to learn how to become desirable, besides she had nothing really to do in her flat aside from reading.
shareShe was jealous of Lisa because Lisa always had a boyfriend, and she probably thought Lisa was more attractive. And of course, this jealousy very much intensifies after Lisa & Matt get together.
Notice how two years later, either Alex is wearing Lisa's (Crimson color tweed) coat, or has bought one just like hers. Imitation is the highest form of flattery.
In the original "L'Appartment" movie, I think Alex (Alice) starts changing herself to look more like Lisa.