I always found that interesting. Troll sweethearts were created to attract and troll Chris, so they had several shared features. To be a troll sweetheart you need to be active/interested enough to keep him on the hook but still able to keep him at arms length. You also want to be demanding enough to make him do weird things.
Despite his professed love for them individually, they were basically variations on a common theme, and obviously, because they were fake, Chris wasn't able to "get to know" any of them. So they all blur together in his mind.
But the real people stick out in his mind. Gal-pals, Megan, etc. In a way, it speaks well of him.