She asked her husband for a divorce at a time of tension. What should she do?

Firstly: 

It is not permissible
for a woman to ask her husband for a divorce unless there is a reason for
that, such as bad treatment on the husband’s part, because of the report
narrated by Abu Dawood (2226), al-Tirmidhi (1187) and Ibn Maajah (2055) from
Thawbaan (may Allaah be pleased with him) who said: The Messenger of Allaah
(peace and blessings of Allaah be upon him) said: “Any woman who asks
her husband for a divorce when it is not absolutely necessary, the fragrance
of Paradise will be forbidden to her.” Classed as saheeh by al-Albaani in
Saheeh Abi Dawood. 

But if she does that
when she is very angry or at a moment of tension, then she has to ask Allaah
for forgiveness. 

A woman should beware of
making a request, for perhaps her husband may become angry and divorce her
out of stubbornness, so her request will become the cause of her family
being broken. 

Moreover, there is
nothing more harmful to married life than the husband or wife’s feeling that
the other party can do without them, and is thinking of getting rid of
them. 

Both spouses must be
patient and use kind words, as enjoined by Allaah (interpretation of the
meaning): 

“And say to My slaves
(i.e. the true believers of Islamic Monotheism) that they should (only) say
those words that are the best. (Because) Shaytaan (Satan) verily, sows a
state of conflict and disagreements among them. Surely, Shaytaan (Satan) is
to man a plain enemy”

[al-Isra’ 17:53]

Secondly: 

If a person gets angry
he should learn how to control it, and he should not say anything under the
influence of anger that he will regret later on. Hence the Prophet
(peace and blessings of Allaah be upon him) advised a man by saying: “Do not
become angry” and he repeated that several times, and he said: “Do not get
angry.” Narrated by al-Bukhaari (6116). 

To learn more about how
to deal with one’s anger, please see question no.
658. 

May Allaah help us all
to do that which He loves and which pleases Him. 

And Allaah knows best.