Consider that they might have mental illness/depression and ignore all these toxic and immature suggestions.

just be a human and have an honest heart to heart with them. If they handle it poorly then they will leave you alone on their own accord. This gives them autonomy and clarity to reflect and change things.

Seriously, dodging, ignoring or being passive aggressive to someone who is obviously going through some stuff is shitty and only prolongs the issue if not makes it worse. Confrontation doesn’t mean you have to argue or belittle, it just means to approach and engage. How you choose to approach is what determines the tone and outcome.

Even if it’s not your responsibility to fix them i think the world would be a much better place if people came from a place of understanding. We are not going to be fun and energetic when we are struggling immensely, and even if the struggle can’t be immediately fixed, honesty and genuineness can go along way to putting things in to perspective for everyone involved.