Can someone please give me hints on normalizing this database and any other helpful hints

Question

I am using Entity Framework 5 to work with this database but I am getting issues with how tblTalkers and tblChatSessions are being mapped in the entity model when imported into Visual Studio. Please let me know if you need more info.

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Here's my DDL for the whole database with the tables as well

USE [master]
GO

/******
    Object:  Database [QuickChatApplication]
    Script Date: 11/17/2012 10:02:15 AM 
******/
CREATE DATABASE [QuickChatApplication]
CONTAINMENT = NONE
ON  PRIMARY 
( 
    NAME = N'QuickChatApplication'
    , FILENAME = N'C:\Program Files\Mi...SQL\DATA\QuickChatApplication.mdf'
    , SIZE = 5120KB 
    , MAXSIZE = UNLIMITED
    , FILEGROWTH = 1024KB
)
LOG ON 
( 
    NAME = N'QuickChatApplication_log'
    , FILENAME = N'C:\Program Files\Mi...SQL\DATA\QuickChatApplication_log.ldf' 
    , SIZE = 2048KB 
    , MAXSIZE = 2048GB 
    , FILEGROWTH = 10%
)
GO

ALTER DATABASE [QuickChatApplication] SET COMPATIBILITY_LEVEL = 110
GO

IF (1 = FULLTEXTSERVICEPROPERTY('IsFullTextInstalled'))
begin
    EXEC [QuickChatApplication].[dbo].[sp_fulltext_database] @action = 'enable'
end
GO

ALTER DATABASE [QuickChatApplication] SET ANSI_NULL_DEFAULT OFF 
GO

ALTER DATABASE [QuickChatApplication] SET ANSI_NULLS OFF 
GO

ALTER DATABASE [QuickChatApplication] SET ANSI_PADDING OFF 
GO

ALTER DATABASE [QuickChatApplication] SET ANSI_WARNINGS OFF 
GO

ALTER DATABASE [QuickChatApplication] SET ARITHABORT OFF 
GO

ALTER DATABASE [QuickChatApplication] SET AUTO_CLOSE OFF 
GO

ALTER DATABASE [QuickChatApplication] SET AUTO_CREATE_STATISTICS ON 
GO

ALTER DATABASE [QuickChatApplication] SET AUTO_SHRINK OFF 
GO

ALTER DATABASE [QuickChatApplication] SET AUTO_UPDATE_STATISTICS ON 
GO

ALTER DATABASE [QuickChatApplication] SET CURSOR_CLOSE_ON_COMMIT OFF 
GO

ALTER DATABASE [QuickChatApplication] SET CURSOR_DEFAULT  GLOBAL 
GO

ALTER DATABASE [QuickChatApplication] SET CONCAT_NULL_YIELDS_NULL OFF 
GO

ALTER DATABASE [QuickChatApplication] SET NUMERIC_ROUNDABORT OFF 
GO

ALTER DATABASE [QuickChatApplication] SET QUOTED_IDENTIFIER OFF 
GO

ALTER DATABASE [QuickChatApplication] SET RECURSIVE_TRIGGERS OFF 
GO

ALTER DATABASE [QuickChatApplication] SET  DISABLE_BROKER 
GO

ALTER DATABASE [QuickChatApplication] SET AUTO_UPDATE_STATISTICS_ASYNC OFF 
GO

ALTER DATABASE [QuickChatApplication] SET DATE_CORRELATION_OPTIMIZATION OFF 
GO

ALTER DATABASE [QuickChatApplication] SET TRUSTWORTHY OFF 
GO

ALTER DATABASE [QuickChatApplication] SET ALLOW_SNAPSHOT_ISOLATION OFF 
GO

ALTER DATABASE [QuickChatApplication] SET PARAMETERIZATION SIMPLE 
GO

ALTER DATABASE [QuickChatApplication] SET READ_COMMITTED_SNAPSHOT OFF 
GO

ALTER DATABASE [QuickChatApplication] SET HONOR_BROKER_PRIORITY OFF 
GO

ALTER DATABASE [QuickChatApplication] SET RECOVERY FULL 
GO

ALTER DATABASE [QuickChatApplication] SET  MULTI_USER 
GO

ALTER DATABASE [QuickChatApplication] SET PAGE_VERIFY CHECKSUM  
GO

ALTER DATABASE [QuickChatApplication] SET DB_CHAINING OFF 
GO

ALTER DATABASE [QuickChatApplication] SET FILESTREAM( NON_TRANSACTED_ACCESS = OFF ) 
GO

ALTER DATABASE [QuickChatApplication] SET TARGET_RECOVERY_TIME = 0 SECONDS 
GO

ALTER DATABASE [QuickChatApplication] SET  READ_WRITE 
GO



USE [QuickChatApplication]
GO

/****** 
    Object:  Table [dbo].[tblChatRooms]
    Script Date: 11/17/2012 10:07:21 AM 
******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[tblChatRooms]
(
    [RoomId] [int] NOT NULL,
    [CreatorsId] [int] NOT NULL,
    [CreatedTime] [datetime] NOT NULL,
    CONSTRAINT [PK_ChatRooms] PRIMARY KEY CLUSTERED 
    (
        [RoomId] ASC
    ) WITH (
        PAD_INDEX = OFF
        , STATISTICS_NORECOMPUTE = OFF
        , IGNORE_DUP_KEY = OFF
        , ALLOW_ROW_LOCKS = ON
        , ALLOW_PAGE_LOCKS = ON
        ) ON [PRIMARY]
) ON [PRIMARY]

GO




USE [QuickChatApplication]
GO

/****** 
    Object:  Table [dbo].[tblTalkers]
    Script Date: 11/17/2012 10:10:39 AM 
******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[tblTalkers]
(
    [TalkerId] [int] NOT NULL,
    [FirstName] [nvarchar](15) NULL,
    [LastName] [nvarchar](15) NULL,
    [ChatAlias] [nvarchar](15) NOT NULL,
    [EmailAddress] [nvarchar](25) NULL,
    [CurrentRoomId] [int] NULL,
    CONSTRAINT [PK_Talkers] PRIMARY KEY CLUSTERED 
    (
        [TalkerId] ASC
    ) WITH (
        PAD_INDEX = OFF
        , STATISTICS_NORECOMPUTE = OFF
        , IGNORE_DUP_KEY = OFF
        , ALLOW_ROW_LOCKS = ON
        , ALLOW_PAGE_LOCKS = ON
    ) ON [PRIMARY]
) ON [PRIMARY]

GO

ALTER TABLE [dbo].[tblTalkers]  WITH CHECK 
ADD CONSTRAINT [FK_tblTalkers_tblChatRooms] 
FOREIGN KEY([CurrentRoomId])
REFERENCES [dbo].[tblChatRooms] ([RoomId])
GO

ALTER TABLE [dbo].[tblTalkers] 
CHECK CONSTRAINT [FK_tblTalkers_tblChatRooms]
GO




USE [QuickChatApplication]
GO

/****** 
    Object:  Table [dbo].[tblChatSessions]
    Script Date: 11/17/2012 10:07:35 AM 
******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[tblChatSessions]
(
    [SessionId] [int] NOT NULL,
    [StartTime] [datetime] NOT NULL,
    CONSTRAINT [PK_ChatSessions] PRIMARY KEY CLUSTERED 
    (
        [SessionId] ASC
    )WITH (
        PAD_INDEX = OFF
        , STATISTICS_NORECOMPUTE = OFF
        , IGNORE_DUP_KEY = OFF
        , ALLOW_ROW_LOCKS = ON
        , ALLOW_PAGE_LOCKS = ON
    ) ON [PRIMARY]
) ON [PRIMARY]

GO



USE [QuickChatApplication]
GO

/******
    Object:  Table [dbo].[tblChatSessionStarters]
    Script Date: 11/17/2012 10:10:20 AM
******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[tblChatSessionStarters]
(
    [ChatSessionId] [int] NOT NULL,
    [StartersId] [int] NOT NULL
) ON [PRIMARY]

GO

ALTER TABLE [dbo].[tblChatSessionStarters]  WITH CHECK 
ADD CONSTRAINT [FK_tblChatSessionStarters_tblChatSessions] 
FOREIGN KEY([ChatSessionId])
REFERENCES [dbo].[tblChatSessions] ([SessionId])
ON UPDATE CASCADE
ON DELETE CASCADE
GO

ALTER TABLE [dbo].[tblChatSessionStarters] 
CHECK CONSTRAINT [FK_tblChatSessionStarters_tblChatSessions]
GO

ALTER TABLE [dbo].[tblChatSessionStarters]  WITH CHECK 
ADD CONSTRAINT [FK_tblChatSessionStarters_tblTalkers] 
FOREIGN KEY([StartersId])
REFERENCES [dbo].[tblTalkers] ([TalkerId])
GO

ALTER TABLE [dbo].[tblChatSessionStarters] 
CHECK CONSTRAINT [FK_tblChatSessionStarters_tblTalkers]
GO



USE [QuickChatApplication]
GO

/****** 
    Object:  Table [dbo].[tblSessionsTalkers]
    Script Date: 11/17/2012 10:10:33 AM 
******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[tblSessionsTalkers]
(
    [SessionId] [int] NOT NULL,
    [TalkerId] [int] NOT NULL
) ON [PRIMARY]

GO

ALTER TABLE [dbo].[tblSessionsTalkers]  WITH CHECK 
ADD CONSTRAINT [FK_tblSessionsTalkers_tblChatSessions] 
FOREIGN KEY([SessionId])
REFERENCES [dbo].[tblChatSessions] ([SessionId])
ON UPDATE CASCADE
ON DELETE CASCADE
GO

ALTER TABLE [dbo].[tblSessionsTalkers] 
CHECK CONSTRAINT [FK_tblSessionsTalkers_tblChatSessions]
GO

ALTER TABLE [dbo].[tblSessionsTalkers]  WITH CHECK 
ADD CONSTRAINT [FK_tblSessionsTalkers_tblTalkers] 
FOREIGN KEY([TalkerId])
REFERENCES [dbo].[tblTalkers] ([TalkerId])
ON UPDATE CASCADE
ON DELETE CASCADE
GO

ALTER TABLE [dbo].[tblSessionsTalkers] 
CHECK CONSTRAINT [FK_tblSessionsTalkers_tblTalkers]
GO




USE [QuickChatApplication]
GO

/****** 
    Object:  Table [dbo].[tblMessages]
    Script Date: 11/17/2012 10:10:27 AM 
******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[tblMessages]
(
    [MessageId] [int] NOT NULL,
    [MessageText] [nvarchar](500) NOT NULL,
    [SendersId] [int] NOT NULL,
    [SessionId] [int] NOT NULL,
    [SentTime] [datetime] NOT NULL,
    CONSTRAINT [PK_Messages] PRIMARY KEY CLUSTERED 
    (
        [MessageId] ASC
    ) WITH (
        PAD_INDEX = OFF
        , STATISTICS_NORECOMPUTE = OFF
        , IGNORE_DUP_KEY = OFF
        , ALLOW_ROW_LOCKS = ON
        , ALLOW_PAGE_LOCKS = ON
    ) ON [PRIMARY]
) ON [PRIMARY]

GO

ALTER TABLE [dbo].[tblMessages]  WITH CHECK 
ADD CONSTRAINT [FK_tblMessages_tblChatSessions] 
FOREIGN KEY([SessionId])
REFERENCES [dbo].[tblChatSessions] ([SessionId])
GO

ALTER TABLE [dbo].[tblMessages] 
CHECK CONSTRAINT [FK_tblMessages_tblChatSessions]
GO

ALTER TABLE [dbo].[tblMessages]  WITH CHECK 
ADD CONSTRAINT [FK_tblMessages_tblTalkers] 
FOREIGN KEY([SendersId])
REFERENCES [dbo].[tblTalkers] ([TalkerId])
GO

ALTER TABLE [dbo].[tblMessages] 
CHECK CONSTRAINT [FK_tblMessages_tblTalkers]
GO