Updatae database with Formview values

CODE BEHIND:
 
 protected void btnUpdateC_Click(object sender, EventArgs e)
    {
        .......................................
        ....................................... // HERE WE NEED TO UPDATE        
        fvSpousal.ChangeMode(FormViewMode.ReadOnly);
        BindSpousalFV();
        SetSpousalMenu("defaultMode");
    }
 
 
SOURCE:
 
<EditItemTemplate>
                <asp:Label ID="lblCoupleSurname_CE" runat="Server" Text="Surname:"></asp:Label>
                &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
                <asp:TextBox ID="txtCoupleSurname_CE" runat="server" Text=<%# Eval("C_Surname")%> />
                &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
                <asp:Label ID="lblMaritalStat_CE" runat="server" Text="Marital Status: "></asp:Label>
                <asp:DropDownList  ID="ddlMarStatus_CE" runat="server" SelectedValue=<%# Eval("C_Mar_Status") %>  >
                   <asp:ListItem Value="M">Married</asp:ListItem>
                   <asp:ListItem Value="D">Divorced</asp:ListItem>
                   <asp:ListItem Value="S">Separated</asp:ListItem>
                   <asp:ListItem Value="W">Widowed</asp:ListItem>
                </asp:DropDownList>     
                &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
                <asp:Label ID="lblWed_CE" runat="Server" Text="Wedding date:"></asp:Label>&nbsp;
                <asp:TextBox ID="txtWedDay_CE" runat="server" Text=<%# Eval("C_Wed_Anniv", "{0:yyyy/MM/dd}") %>  
                Width="70px" />
                <div style="height:5px;"></div>
                <asp:Label ID="lblEmail_CE" runat="Server" Text="Email: "></asp:Label>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
                <asp:TextBox ID="txtEmail_CE" runat="server" Text=<%# Eval("C_Email") %>  Width="375px"  ></asp:TextBox>
                <div style="height:3px;"></div>
                <asp:CheckBox ID="chkActive_CE" runat="server" TextAlign="Left" Text="Current in ME&nbsp;&nbsp;" Checked=<%# Eval("C_Active") %> 
                	/>
 .....................................
.......................................

                                  

1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:
21:
22:
23:
24:
25:
26:
27:
28:
29:
30:
31:
32:
33:
34:
35:
36:
37:
38: