Got hit by a car while on my bike. Any advice?

I am looking for anyone in the Austin area who has had to deal with being hit by a car while riding their bike. I have been contacted by the drivers insurance company and they are telling me that I am 50% liable for my medical bills because they believe we are "equally liable". I want to fight this and I need a little bit of guidance. Does anyone have any experience? Or perhaps the name of a good personal injury lawyer in the area? Thank you for any help you may be able to provide.