eh, Diet Coke is primarily water, aspartame, phosphoric acid and caffeine. I drink 5/6 of them a day (don't like water much). The paper linked actually says short term effects of diet soda are less problematic, but recent evidence suggests that aspartame may have harms on the microbiome and glucose tolerance generally.
That said, the idea of drinking anything either sweet or carbonated before bed, during the night, or in the morning, mind boggling to me, that does sound really gross.
Have you ever tried plain carbonated water? It's more interesting than still water, and for me more thirst quenching. Easy to make at home with a Soda Stream or similar, just don't add any of their syrup.
That said, the idea of drinking anything either sweet or carbonated before bed, during the night, or in the morning, mind boggling to me, that does sound really gross.