Publisher- and if the OP’s parents decide to apply to college, their story might make a very compelling essay. But for the OP to devote limited real estate to explaining and describing a struggle with addiction which is second hand seems to be a stretch.
OP- talk about you. If there are family issues which you need to allude to in order to round out your story, then fine. The issue isn’t whether an essay is “risky” and you’re looking for a college which is OK with a risky back story. The issue is that writing an entire essay about your parents doesn’t answer the question “what will this student add to campus”.