I'm sorry for your loss. That must have been hard for you. However, as you know, it's not an excuse for academic dishonesty.
Although I concede that grief is briefly crazy-making, I wonder, why did you not reach out to anyone (your advisor, professor, TAs, friends, etc.) when you were in trouble?
I suspect, that even if you were able to overcome this hurdle, that schools will wonder this too, and would like to know what you learned from the situation and how you would handle yourself should an event like this arise again.
Best of luck.