Django Form context data lost on validation fail

My form (code below) loads and saves fine. However, if there is a validation error in the form and it is reloaded, the context['uploaded_files'] which I assign in the get_context_data method is empty. Why is that and how can I once again pass the context['uploaded_files'] it when the form is reloaded on validation fail?

class BusinessEditView(UpdateView):
    template_name = 'directory/business_edit.html'
    model = Appuser
    form_class = BusinessEditForm

    def get_context_data(self, **kwargs):
        context = super(BusinessEditView, self).get_context_data(**kwargs)
        user_object = context['appuser']
        files = [user_object.logo]
        context['uploaded_files'] = files
        return context

    def get_object(self, queryset=None):
        return self.request.user

    def post(self, request, *args, **kwargs):
        form = BusinessEditForm(request.POST, instance=self.request.user)
        if form.is_valid():
            form.save(commit=False)
            return HttpResponseRedirect('/profile/')
        else:
            return render_to_response('directory/business_edit.html', {'form': form}, context_instance=RequestContext(request))

As per @Alasdair's suggestion, I amended the else clause as follows:

context = self.get_context_data()
return render_to_response('directory/business_edit.html', context, context_instance=RequestContext(request))

It however, caused an exception as follows:

Traceback:
File "/Users/h/.virtualenvs/pony/lib/python2.7/site-packages/django/core/handlers/base.py" in get_response
  111.                     response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/Users/h/.virtualenvs/pony/lib/python2.7/site-packages/django/views/generic/base.py" in view
  69.             return self.dispatch(request, *args, **kwargs)
File "/Users/h/.virtualenvs/pony/lib/python2.7/site-packages/django/views/generic/base.py" in dispatch
  87.         return handler(request, *args, **kwargs)
File "/Users/h/Development/Pony/pony/directory/views.py" in post
  296.             context = self.get_context_data()
File "/Users/h/Development/Pony/pony/directory/views.py" in get_context_data
  272.         context = super(BusinessEditView, self).get_context_data(**kwargs)
File "/Users/h/.virtualenvs/pony/lib/python2.7/site-packages/django/views/generic/detail.py" in get_context_data
  100.         if self.object:

Exception Type: AttributeError at /profile/business/edit/
Exception Value: 'BusinessEditView' object has no attribute 'object'