Try running just the following stripped-down code. It should produce a series of new documents - one per Section of your source document, with just one copy of each Section's content per new document.
Code:
Sub emailmergewithattachments()
Dim Source As Document, wdDoc As Document, oRng As Range, j As Long
Set Source = ActiveDocument
For j = 1 To Source.Sections.Count - 1
Set wdDoc = Documents.Add
Set oRng = wdDoc.Range
oRng.Collapse 1
'oRng.FormattedText = Source.Sections(j).Range.FormattedText
Source.Sections(j).Range.Copy
oRng.Paste
Next j
MsgBox Source.Sections.Count - 1 & " messages have been sent."
End Sub