Delphi Unique Dynamic Form Creation - forms

Question

I am using multiple forms on my project. (Client Server Application) I used chat but i have some problems.
1- I have a user list on my listview. And i am open new chat form here.
procedure CreateNewChat(User: String);
var
ChatForm: TChatForm;
begin
ChatForm:= TChatForm.Create(nil);
if assigned (ChatForm) then
ChatForm.User:= User;
Chat.Socket:= MySocket; // TClientSocket new Instance
ChatForm.Show;
end;
///Chatform
procedure ParseData(Cmd:string);
begin
if Cmd <> '' then
begin
/// parsing...
end;
New connections are adding to listview like that
var
Item: TListItem;
NewTempForm: TTempForm;
begin
NewTempForm := tempForm.Create;
Item := Listview.Items.Add;
if User = '' then
Exit;
Item.Caption := User;
Item.SubItems.Add('OK');
Item.GroupId := GroupId;
Item.SubItems.Objects[0] := NewTempForm;
end;
My problems are started on here.
1- How can i detect form according to user? So, if two or higher form is open then how can i show received message on them? Because i was create them dynamically. I need a object for detect.
I tryed like that
var
tempForm: TTempForm; // this is an empty object class
sTempStr: String;
begin
if ListView.Selected <> nil then
begin
tempForm := TTempForm(ListView.Selected.SubItems.Objects[0]); // this is for unique form creation
if tempForm.frmTasks = nil then // if there is not, create!
begin
tempForm.frmTasks := TfrmTasks.Create(nil);
end;
But my received message is appear on all forms. Actually should appear just one form. (Which user sent it)
Thanks.