Hit by a horse when I was stationary

Can anyone help me. I was driving home after dropping my wife to the hospital. When I was hit by a horse I seen the horse coming so I stopped thinking it would go around me. But it didn't it ran straight into the front of the car causing a lot of damage. There was no rider on it at the time. The problem I got is it was my friends car I was driving as mine is being repaired in the garage. So I am only third party on the vehicle. I have spoken to my insurance and they won't help so I went to a solicitor and because I have not hurt myself they won't help either. I don't know what to do.

Thanks
Rob