When a girl (wife) become maharam or haaraam for her husband?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

In principle, a husband and wife remain married and a wife does not become forbidden for her husband unless something which entails a separation between them takes place such as divorce, or Li’aan. Li’aan, which is when both spouses make an oath that he/she is truthful in his/her claim and then invoke the curse of Allaah on the one who is lying. This takes place when the husband accuses his wife with adultery, and is done in front of the ruler or the judge. By invoking this curse on each other, the wife becomes permanently forbidden for her husband.

Similarly, Thihaar, which is the saying of the husband to his wife "You are like my mother to me", meaning that ''You are forbidden upon me exactly like my mother'' then his wife becomes temporary forbidden until he expiates his sin in accordance with the saying of Allaah (which means): {And those who make unlawful to them (their wives) (by Thihaar) and wish to free themselves from what they uttered, (the penalty) in that case (is) the freeing of a slave before they touch each other. That is an admonition to you (so that you may not return to such an ill thing). And Allaah is All-Aware of what you do. And he who finds not (the money for freeing a slave) must fast two successive months before they both touch each other. And for him who is unable to do so, he should feed sixty of poor people.}[Quran 58:3].

Additionally, it should be noted that a husband may be forbidden from having sexual intercourse with his wife while she is still considered his wife, for instance, when she is in menses or in post partum bleeding, as Allaah Says (what means): {They ask you concerning menstruation. Say: that is an Adha (a harmful thing for a husband to have a sexual intercourse with his wife while she is having her menses), therefore keep away from women during menses and go not unto them till they have purified (from menses and have taken a bath). And when they have purified themselves, then go in unto them as Allaah has ordained for you (go in unto them in any manner as long as it is in their vagina).}[Quran 2: 222].

To conclude, it should be noted that if the divorce is revocable, like the first or second divorce, then it is permissible for the husband to go back his wife as long as she is in her waiting period, but if her waiting period finished, he can re-marry her but with a new marriage contract. However, if it is the third divorce, then she becomes forbidden for him until she marries another man who divorces her after consummating the marriage with her. Consequently, her first husband may re-marry her [with a new contract and a new dowry], after she observes the waiting period of her divorce from her second husband.

Allaah Knows best.