What fields do you have in your data source that would identify the
partners?
Normally you would have something along the lines of spouse surname and
forename fields. You can then use conditional fields to place the correct
data eg
{IF {Mergefield LastName} <> {Mergefield Spouse_Lastname} "{Mergefield
Title} {Mergefield FirstName} and {Mergefield Spouse_Title} {Mergefield
Spouse_FirstName} {Mergefield Spouse_LastName}" "{Mergefield Title} and
{Mergefield SpouseTitle} {Mergefield FirstName} {Mergefield LastName}"}
If some of the recipients are single and have no partners then the second
part of the condition requires a further condition eg
{IF {Mergefield LastName} <> {Mergefield Spouse_Lastname} "{Mergefield
Title} {Mergefield FirstName} and {Mergefield Spouse_Title} {Mergefield
Spouse_FirstName} {Mergefield Spouse_LastName}" "{IF {Mergefield
Spouse_LastName} <> "" "{Mergefield Title} and {Mergefield SpouseTitle}
{Mergefield FirstName} {Mergefield LastName}" "{Mergefield Title}
{Mergefield FirstName} {Mergefield LastName}" }

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Graham Mayor - Word MVP
My web site www.gmayor.com
Word MVP web site http://word.mvps.org
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> I am trying to mail merge a document to several women who use their
> maiden name and their husbands.
[quoted text clipped - 6 lines]
>
> Dear Jim and Jan,