Not an ordinary walk

It's been one day since I experienced the traumatic event of my dog, Jo, being attacked by another dog on our morning walk.  I felt an incredible powerlessness as I was unable to rescue my dog from the attacking dog.  I debated about letting go of my dog's leash so she could run or fight back but decided that if I let go she would be killed.
I remained holding her leash watching this viscous attack as I  frantically kicked the attacker and screamed for help at the top of my lungs over and over for what seemed like a really long time. I sensed the amazing stillness and calm all around me as no human was in sight.  I felt like I was in a vacuum as I pleaded repeatedly for help, kicking with all my might, and watching my innocent pup be aggressively attacked over and over. I felt so alone, inadequate, and powerless.
By this time my dog and I have been pulled off the street and into the ditch of the neighbor's yard by the agressor. Eventually the neighbor must have heard me and a young woman came running toward us and started to frantically but futilly pound on the dog with her arms and kick with her legs as she screamed at "Echo", the aggressive attacking dog to stop. Soon the young woman's father came running out with bare feet, perhaps awakened from sleep.  He also yelled and swung his arms and bent between the two dogs to quickly have his hand bit by my dog, the victim.  He stood up and came behind his dog, continuing to yell. He placed his arms under the attacking dog's belly behind the front legs and pulled with all his might to eventually pull the dog off of my dog as they landed with a thud on the ground. The two neighbors quickly whisked away "Echo" to secure him somewhere away from us.
Jo and I crumpled into the ditch and I held her and told her, "It's over now!" We, both in shock, felt stunned  at what had happened.
I am of the belief that things don't just randomly happen for the most part and that there are great lessons/opportunities in what happens in our lives.  I am sensing there is so much to glean from this lesson of victim/aggressor....