Well, that's a wide field really.
IMO Any kind of addiction aims to suppress the emotions you are feeling at that moment.
Of course drugs and alcohol but also social media, gambling and simply sleep.
It's a way to override temporarily the brain functions that make you feel bad/sad/angry etc. and replace those feelings with euphoria/happiness/joy/relaxation or at least a neutral feeling that doesn't hurt.
In the end, many of us are trying to find an escape from pain. Mentally or physically.