Things Got Physical

Recently, my sister said her friend was available to drive my Mom to one of my Mom's medical appointments, however, when she arrived she was combative with me and she physically fought me on the sidewalk in front of my Mom's apartment building. The whole thing was surprising and hurtful to me... she immediately said to anyone within earshot that it was my fault... that I had a bad attitude, I started it, I put hands on my Mom, and I fought her (ALL UNTRUE) God had my back that day because while this was happening my Mom's friend and neighbors pulled up in their car and saw the end of it and when I saw them I began screaming their name to come and help me... they did and they heard what she had to say but because they know us they know that it wasn't true. Now, I'm left to deal with what happened that day and I am hurt about it and I don't know how to proceed because the person that hurt me is at this time considered a family friend. Please help me figure out how to deal with this going forward.