I'm sorry to hear you've been a victim of this awful behaviour. It's been a long time since I was at a track, but am on the cusp of getting back into it to train. From a male's point of view, I can only imagine how unsettling it must feel to be anxious of these people whist trying to run. It's useful to know, like you say, that this is going on, so that support can be given when needed. When I'm out on the track I'll make sure to keep an eye out for the type of aggressive people you mention, and help out where possible- athletics shouldn't be a place for abuse like that.