undefined method `requested?' for nil:NilClass

 <div class="page-header">
         <h1> Viewing Friendship </h1>
 </div>

 <% if @user_friendship.requested? %>
     <h3> Do you really want to be friends with <%= @friend.name %>?</h3>
 <% end %>


 <div class="form-actions">
     <% if @user_friendship.requested? %>
    <%= form_for @user_friendship, url: accept_user_friendship_path(@user_friendship), method:
        :put do |form| %>
        <%= submit_tag "Accept Friendship", class: 'btn btn-primary' %>
         <% end %>
     <% end %>
 </div> 

     class UserFriendshipsController < ApplicationController
    before_filter :authenticate_user!

    def new
      if params[:friend_id]
        @friend = User.find(params[:friend_id])
        raise ActiveRecord::RecordNotFound if @friend.nil?
        @user_friendship = current_user.user_friendships.new(friend: @friend)
      else
        flash[:error] = "Friend required"
      end
    rescue ActiveRecord::RecordNotFound
      render file: 'public/404', status: :not_found
    end


    def create
      if params[:user_friendship] && params[:user_friendship].has_key?(:friend_id)
        @friend = User.find(params[:user_friendship][:friend_id])
        @user_friendship = current_user.user_friendships.new(friend:  @friend)
        if @user_friendship.save
          flash[:success] = "You are now friends!"
        else
          flash[:error] = "There was a problem."
        end
        redirect_to user_path(@friend)
      else
        flash[:error] = "Friend required"
        redirect_to root_path
      end
    end


    def index
      @user_Friendships = current_user.user_friendships.all
    end

     def accept
       @user_friendship = current_user.user_friendships.find(params [:id])
       if @user_friendship.accept!
        flash[:success] = "You are now friends with #  {@user_friendship.friend.name}"
      else
        flash[:error] = "That friendship could not be accepted"
       redirect_to user_friendships_path
    end


     def edit
       @user_friendship = current_user.user_friendships.find(params [:id])
       @friend = @user_friendship.friend
     end

     def user_friendship
     params.require(:user_friendship).permit(:user_id, :friend_id, :user, :friend, :state, :user_friendship)
     end



  end
  end