And because so many people were confused about the plot of New Moon...
Astro and Dandy had a brief falling out due to an unspecified incident (I never planned it out), putting a strain on their relationship. So, in his rage, Dandy created a new one. He planned to groom them into the perfect partner, a shallow and transactional relationship where he had all the control, but of course, the original Astro wasn't ever going to let that side. Not only was Dandy just straight up cheating, but Astro is possessive. That's his (boy)friend.