When it comes to love, I've had a series of problems finding someone who truly appreciates just how wonderful I am, which has led to a couple of relationship disasters, including a divorce.
Now I realize that my wonderfulness is best doled out in small doses, or maybe even just kept completely to myself.
Despite the fact that your daughter is still your little girl, when she looks in the mirror, she sees a full-grown women, one she apparently feels is ready to get married to some loser. Just because he asks you how things are going at work doesn't mean he's mentally tabulating your net worth because he's planning to steal your money and sack your village.
Just because he kisses your daughter doesn't mean he's an alien being, intending to impregnate her with a creature that will burst out of her chest and destroy mankind.* On the other hand, all three of the above are reasonable suspicions that should be investigated via polygraph and liver biopsy, and if he refuses, he should not be marrying your daughter.
Unfortunately, even if you get rid of this one, others will soon follow -- people have been irresponsibly breeding boys for a long time, and why this isn't prevented by the Geneva Convention, you'll never understand.
With my glorious male wonderfulness thus in check, I've managed to find and keep a steady girlfriend for a couple of years, though she's just off a nasty breakup herself, so we're both proceeding with caution. What a perfect age for my daughters to start contemplating getting married!