Only lobsters mate for life

In the year and a half that I have known my roommate, she has been seriously involved with four men. Not all at the same time, of course (though there was some overlap between #2 and #3, come to think of it). But four. In 18 months.

She started out engaged to one, then broke up with him and started dating #2, which ended up badly, with tears and chocolate, and in the meantime, #3 was sort of a brief fling. Now - ha! - now she's pregnant with #4's baby. But hey, she says she's in love, and that this is the man she's going to spend the rest of her life with.

I feel like I've been living with an alien. Not only do I not understand what she sees in these people, I don't understand how she sees so many of them and manages to develop such strong feelings for them so quickly. Boyfriend #4? She's only known him for about three months! How can she possibly know she wants to spend the rest of her life with him and have his baby?

Don't get me wrong; this isn't an entry all about judging my roommate's questionable choices in men. It's the whole situation that's baffling to me. In talking about her relationships, she displays exactly the kind of behaviour I think people are expected to display, and it only serves to frighten me. When her knees physically buckle as she describes her boyfriend's physique, or she talks about how she feels sick and can't think straight when he's not with her, she sounds like every pop song ever written over the past fifty years, and I can't say that I have the faintest idea what she's talking about.

Is that sexual attraction? Is that what it feels like? Is that what it does to you? My roommate's serial dating aside, I wonder if this is what the world at large means when it uses words like "love" and "desire" and "want."

I feel like such a stranger.