Wow i guess that sucks. Part of driving is anticipating things like that though. No one expects you to because you are on your L's and you didnt do anything wrong, but an experienced driver knows not to leave much of a gap in case idiots try something like this. Something similar happened to me when i had my L's except i didnt hit him [ i had stopped in the middle of the road to turn like you, right hand traffic meant he couldnt overtake on the right so the idiot went around on the left]
Its a pretty shit wake up call though. I wish you didnt have to learn the hard way about insurance, but basically you get it to avoid situations were other people are fuckwits, not because you think you will have an accident where its your fault.
My driving instructor had someone fuck her over with insurance, and even if you win the court case, it will be like getting blood out of a stone.
It sucks, but if you take some steps now i.e lawyer up, photos etc then this doesnt have to be as big of a headache as you think.