Short answer. No. Civil Code Article 383 gives the present spouse preference to be appointed representative only when there is no legal separation. If you are legally separated from the absentee, that preference does not apply to you, and the court is free to appoint any other competent person instead.
What the law says
In the appointment of a representative, the spouse present shall be preferred when there is no legal separation.
Civil Code, Article 383 — Spouse Preferred as Representative. Read the full provision →
The spouse's preference, and its condition
Article 383 sets a default preference for who should manage an absentee's property: in the appointment of a representative, the spouse present shall be preferred when there is no legal separation. The word 'present' distinguishes the spouse who remains from the one who has gone missing, and the preference exists because a spouse is ordinarily assumed to have both the closest interest in the absentee's affairs and firsthand knowledge of their property. But the text builds a condition directly into the preference itself: it only applies where there is no legal separation between the spouses.
What legal separation does to that preference
Because the preference is conditioned on the absence of legal separation, a spouse who has obtained a decree of legal separation from the absentee does not carry it. Legal separation formally recognizes that the marital relationship has broken down to the point that the couple no longer lives together as husband and wife, and the law does not extend the same automatic trust in managing the other spouse's property to someone in that position. The court is not barred from appointing you, but it is not required to prefer you either, the way it would a spouse with no legal separation between them.
Who the court can appoint instead
Article 383 also addresses what happens when the spousal preference is unavailable: if the absentee left no spouse, or if the spouse present is a minor, any competent person may be appointed by the court. A legally separated spouse falls outside the situation the preference was written for, so the appointment becomes a matter for the court's judgment among competent candidates rather than a preference running automatically in either direction. Anyone the court considers competent to manage the absentee's property responsibly, family member or otherwise, may be named.
Why this rule exists in the context of absence
This article sits within the Civil Code's provisions on a person's declared absence, which deal with managing property left behind by someone whose whereabouts are unknown. The representative's job is to safeguard and administer that property while the absentee's status is sorted out, which is why the preference ordinarily runs to the spouse: administering a missing person's affairs calls for a level of trust and shared interest the law assumes a spouse has. Removing that assumption once legal separation has intervened protects the absentee's property from being managed by someone the law no longer treats as standing in that close a relationship.