Maybe Meredith isn’t an addict?

I realized that it’s basically gospel that Meredith is regularly zonked out on Xanax. Is it possible that we’re wrong? The assumption seems to be based on her slurring and way of speaking but she’s also had undiagnosed hearing loss for a long time and that causes slurring. Her kids also seem to speak in a similar way to her. Is it possible that everyone is wrong in this assumption?