Advice on a table structure - Mailing list pgsql-novice

I have one table that stores data about persons with fields like:

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PERSONS TABLE

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* Id

* Last name

* First name

* Gender

* Marital status

and other information that relates to a single person.

One person might have a husband if female, or a wife if a male. So I thought about adding a table that associates couples like this:

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COUPLES TABLE

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* Id

* Husband (represents an Id of PERSONS table)

* Wife  ( represents an Id of PERSONS table)

One restriction is that one person cannot have more than one spouse.

I also thought about adding a field to the PERSONS table specifying his/her spouse but it seems to me that this approach represents a kind of "circular" relation between 2 records.

I am writing to ask for advice about an optimal approach to model this situation.

Respectfully,

Jorge Maldonado