I know this is probably a common topic. For me, I’m not sure if it’s a “trope” or just totally misinformed writing, but it’s how many authors approach alcoholism. Some examples are Girl on the Train and The House Across the Lake, among HUNDREDS. If anyone else here has struggled with alcoholism, you know it’s not just "i woke up after downing an entire bottle of whiskey but was able to shower, down a cup of coffee, and solve a murder. "
There is a Ruth Rendell novel, The St. Zita Society, where this happens. But it’s darkly humorous. Two people saw it happen, and they go through all this farce of moving the body, moving it again, lying to the police, lying to people they know…And one of them does point out that they could have just said “There’s been an accident” and then stepped back.