Well, in a practical sense, it's quite challenging. You might be able to limit your exposure to certain types of stories, but completely hiding from all of them is nearly impossible. Maybe by staying away from media and social interactions, but even then, stories can still find their way to you.
There could be various reasons. Maybe she wants to work through it on her own first. Or it might involve something she's not proud of and is worried about your reaction.
There could be various reasons. Maybe it was a personal moment she wanted to keep just for herself or a few close friends. Or maybe she's going through something and doesn't want to share it widely yet.
To hide comments from a story, first, explore the menu or options available. Maybe there's a 'Comments' section where you can find a 'Hide' or 'Disable' button. Also, some platforms might have it in the account settings related to content display preferences.