I think it's nearly impossible for a single card to answer a question. For me, a reading is a story, and one card would be like a sentence fragment, especially a card as complex as The Moon. So, as an outcome, I'd say it heralds a disturbing time in the relationship. It doesn't speak to endings. So, if the relationship already exists, there's no reason to believe it would be severed. If it's a relationship that doesn't exist, it does, however, speak to delusions, so that'd be bad. To me, The Moon and The Sun are always connected, so it has some of the positive energy of The Sun just weakened and hidden.
What is your personal definition of The Moon? How do you normally read it? And how can you apply it in context? If your feeling, based on the answers to those questions is, "This ends badly" then I say, go with that.