Stack level too deep or unknown attribute: password_confirmation - ruby

Question

I'm working on a web app that has users model. You either sign up or try the app and be a 'guest'. I had the sign up functionality working well until I added the guest option. I based on Railscast to do this (http://railscasts.com/episodes/393-guest-user-record) and that's when I ran into troubles
Here is my user model code
class User < ActiveRecord::Base
attr_accessible :name, :email, :password, :password_confirmation
has_many :bookings
has_one :account, dependent: :destroy
# before_save :downcase_email, allow_nil: true
before_save :create_remember_token
validates_presence_of :name, :email, :password, :password_confirmation, unless: :guest?
validates_uniqueness_of :email, case_sensitive: false , allow_blank: true
validates :name, length: { maximum: 50 }
VALID_EMAIL_REGEX = /\A[\w+\-.]+#[a-z\d\-.]+\.[a-z]+\z/i
validates :email, format: { with: VALID_EMAIL_REGEX }, unless: :guest?
validates :password, length: { minimum: 6 }, unless: :guest?
def downcase_email
{ |user| user.email = email.downcase }
end
# has_secure_password
# override has_secure_password to customize validation until Rails 4.
require 'bcrypt'
attr_reader :password, :password_confirmation
include ActiveModel::SecurePassword::InstanceMethodsOnActivation
##def to_param
## "#{id}.#{name.parameterize}"
##end
def self.new_guest
new { |u| u.guest = true }
end
def name
guest ? "Guest" : name
end
private
def create_remember_token
self.remember_token = SecureRandom.urlsafe_base64
end
end
and here is my User Controller code:
class UsersController < ApplicationController
before_filter :signed_in_user, only: [:edit, :update]
before_filter :correct_user, only: [:edit, :update]
def show
#user = User.find(params[:id])
end
def new
#user = User.new
end
def create
#user = params[:user] ? User.new(params[:user]) : User.new_guest
if #user.save
sign_in #user
#user.create_account.accountPlan = "Free"
##flash[:success] = "Welcome to the HighTide!"
redirect_to #user
else
render 'new'
end
end
def edit
#user = User.find(params[:id])
end
def update
#user = User.find(params[:id])
if #user.update_attributes(params[:user])
#flash[:success] = "Profile updated"
sign_in #user
redirect_to #user
else
render 'edit'
end
end
private
def correct_user
#user = User.find(params[:id])
redirect_to(root_path) unless current_user?(#user)
end
def admin_user
redirect_to(root_path) unless current_user.admin?
end
end
you may notice some code is commented out. I wasn't able to store in the database a user without an email (and for have a quick and dirty thing working now I comment the callback before_save, I also might add that I use the guidelines of Michael Hartl tut)
What happens is, when I run this code I get a unknown attribute: password_confirmation error, but when I comment out
require 'bcrypt'
attr_reader :password, :password_confirmation
include ActiveModel::SecurePassword::InstanceMethodsOnActivation
and use has_secure_password instead
I get a stack level too deep
I haven't figured out what to do