Having trouble associating two users when adding a friend

Thanks for visiting

Whenever I click on Add a friend I get "friend added" but upon checking my console it says Friendship id: 10, user_id: 2, friend_id: 0, created_at: "2015-09-11 05:05:27", updated_at: "2015-09-11 05:05:27"> meaning it's adding but not associating with a friend_id. Can someone help me figure out why it's not saving friend_id whenever I click add a friend. Thank you for all your help.

Schema.rb

create_table "friendships", force: true do |t|
    t.integer  "user_id"
    t.integer  "friend_id"
    t.datetime "created_at"
    t.datetime "updated_at"
end

Routes.rb

root "users#index"

  resources :friendships, only: [:create, :destroy]
  resources :sessions, only: [:new, :create, :destroy]
  resources :users

Users/show

<% @users.each do |user| %>
 <% if user.user_name != current_user.user_name %>
  <% if @friendshiplink.nil? %>
   <%= user.user_name %>
   <%= link_to "Add Friend", friendships_path(friend_id: user), method: :post %>
  <% else %>
   <%= link_to(
       ("Unfollow"),
      "/friendships/#{ @friendshiplink.id }",
      method: :delete) %>
  <% end %>
 <% end %>
<% end %>

User Model

has_many :friendships
has_many :friends, through: :friendships
has_many :inverse_friendships, class_name: "Friendship", foreign_key:  "friend_id"
has_many :inverse_friends, through: :inverse_friendships, source: :user

Friendship Model

belongs_to :user
belongs_to :friend, class_name: "User"

User Controller

def show
 @users = User.all
 @user = User.friendly.find(params[:id])
 current_user
 if @current_user
    @followerlink = Follower.where(leader_id: @user.id,
                             follower_id: @current_user.id).first
    @friendshiplink = Friendship.where(user_id: @user.id,
                                friend_id: @current_user.id).first
 end
end

Friendship Controller

def create
 @friendship = current_user.friendships.build(friend_id: params[:friend_id])
 if @friendship.save
  flash[:notice] = "Added friend."
  redirect_to root_url
 else
  flash[:error] = "Unable to add friend."
  redirect_to root_url
 end
end

def destroy
 @friendship = current_user.friendships.find(params[:id])
 @friendship.destroy
 flash[:notice] = "Removed friendship."
 redirect_to current_user
end

def friendship_params
 params.require(:friendship).permit(:friend_id, :user_id)
end

Thanks again for all the help. If there are any question or I'm missing a part of my code which may be needed, Please ask.