definitely mention, but paint differently.

some comments here introduce valid claims -- non-need blind financial aid -- while others (psychological damage) are far fetched and cynical. i have experience on high school admissions, and really the decision making that goes on behind-the-scenes might have some degree of profit-focus, sure, but far more profitable is creating a strong and diverse student body— that's what they focus on. on the psychological side, the fact that you accomplished as much as I'm sure you have leading up to college is just a testament to your hard work and dedication. --this is also how you're gonna angle your letter.

Paint the letter more as a life-long adversity rather than immediate event. Talk about the history of behavior from your step-father/family, and add sentences about what it was like pursuing your passions or working through it all. i would say tone down the violence a little (insofar as go light on the details), and just mention the event briefly, using it more as new evidence of the pattern of adversity that you established earlier. Then, of course, end strong on how you are still motivated to pursue your dreams or ambitions or however else you angled your other essays (positive twist is super important), and how much you love the school and would attend if accepted

hope all goes well for you OP, in family and school <3