Michelle,
Wow...I know I would have felt the same way. I had already decided yesterday that I need to write a book for young ladies these days, they are all so confused. Even ones who are 28 and 30, students I worked with, are having real issues in this area, and it's very frustrating. I'm finding they are really reluctant to grow up or to commit to anything but lifelong career or study. Perhaps you could explain to your daughter that whenever you transact any business in this world a good contract (commitment) is required, whether to take on a job, or to purchase a car, or to get insurance, or to go to university. But when you're talking flesh and blood, you need something much more personal (a bodily commitment, not to be broken)...and when you're talking spirit to spirit, and joining those with the Spirit (for blessing), you're talking a covenant. Does that make sense?
I also wonder how much understanding there is of 'spirit', even of kids coming out of Christian schools. Also, because of the fact that contracts are easily broken at times, perhaps the concept of an unbreakable commitment of flesh to flesh and spirit to spirit is watered down and not really understood.
I think you also need to discuss the seriousness of how a person is to treat another, and how that relates to marriage. Kids growing up in an age when you can take a car home from the lot but if you don't like everything about it you can take it back and get another, or you can bring a blouse home from the store but if it bores you the first time you wear it you can just return it - this makes a generation feel that they can treat one another the same way. The concept of permanence, commitment, building a future together, working together for one goal and purpose, etc....all of this seems to be foreign to them. Perhaps you can relate it to the importance of teamwork on a job, and the blessings (benefits) that come from staying at one company for life rather than moving from one to another.
Then, God, too, has committed Himself to us permanently, forever. He has made a covenant with us, and many promises, saying that 'He will never leave us nor forsake us.' He asks one thing of us, and that is our commitment to Him, to love Him with everything in us, forever, permanently.
Maybe this will help,
Beta