So again, just to be very blunt, the most selective colleges get a lot of applications from kids with perfect or near-perfect grades, and they are going to reject most of those because they have no choice. They don’t have nearly enough room for them all.
And they know lots of those kids faced serious adversity at one point or another in HS, because things happen–divorces, deaths, illnesses, and so on. But that stuff happens in college too, and so their ideal applicant faced such adversity and managed to continue to perform consistently in school anyway.
I am mentioning this not to discourage you, but to help you make realistic plans. It is just asking a lot for them to pick you in these circumstances, when they know they are already going to be rejecting lots of kids who overcame a lot of adversity, and they still don’t have room for them either.
Which doesn’t mean they never make exceptions in such circumstances, but I think it is very, very rare for them to do that, and basically only if you really give them some other compelling reason to admit you. Like, they absolutely love what they read in your recommendations and essays, and they really want to admit you, but your grades are not up to their normal standards, but they are satisfied this won’t be a repeat problem, so they go ahead and take you.
But if they didn’t already really want to take you, I don’t think that is a very realistic story anymore. Not at the most selective colleges.
Again, the point of all this is that I really think you need to focus on writing the best possible applications for some select colleges where you really believe they would be a great fit for you, AND you would really be a great fit for them. Give them your best pitch, and hope they think the same thing.
And hopefully your counselor or perhaps a teacher can discuss the adversity you faced. But the main point of what you do would not be trying to get an excuse for those grades, but instead giving them some other reason to think they just have to have you at their college.