Please show me correct path to repent myself for the sin I had done. I am married person with 3 children I love my family from my heart, but I had a problem with my wife from past 10 years that she will be fighting with me for every small things in life. I got fed up with her and was upset and out of mood. I don't want to give more stories about it and want explain what happen next. One poor girl was working in our house as house maid and she was sincere and with good character. No one from her family used to visit her so she was whole and sole with us. Some who she started loving me and one day I slept with her and from that day whenever we had chance we used to be together. I don't want to explain to you about my character because whatever I am I had done sin front of Allaah. Just before 1 month I made her marriage to one person but I came to now at the time of marriage she was pregnant. Once I came to now about this I don't now what happen to me whatever I do wherever I go some has started bothering me and I am crying day and night and even in my Namaaz. So brother I want to now some answer about my sinful story I hope I will get the correct advice from you where at least now I can repent for my sinful act and ask forgiveness from Allaah.
1. The marriage which took place, is Halaal or Haraam because she was pregnant at the time of marriage?
2. What I have to do to correct it?
3. I am ready to marry her if her husband leaves her?
4. Do I have to inform her husband about our relationship but along with this I don't want any one Izzath to be on road.
5. I had done sin but not her because she is very innocent girl and I don't want to bring her Izzath out.
6. About the child which is in her womb what I have to do with it. I am ready to give my name but till I marry again with her how she has to live with her husband?
7. Please guide me in correct direction how I have to settle this problem?

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.

Adultery is one of the greatest and most obnoxious sins. Generally, a person is dragged to it by being too tolerant about the causes that lead to it, like being in seclusion with a woman, forbidden mixing and so forth. One of the most dangerous of these causes is failing to observe the religious requirements when employing a female servant at home. So you have to sincerely repent to Allaah, perform good deeds as much as possible and avoid any reason that could lead you to commit adultery again.

As regards the other issues that you raised in your question, the answer will be as follows:

1)     The jurists differed in opinion with regard to marrying a pregnant adulteress. The Maaliki and Hanbali schools are of the view that it is not permissible to marry her [the marriage to her is invalid]. However, the Hanafi and Shaafi'ee schools are of the view that it is permissible to marry her. So according to the second opinion, the marriage that is mentioned is valid but it is not permissible for this man to have sexual intercourse with her until she gives birth to the baby. The evidence is the narration of the Prophet as he said: "It is not permissible to have sexual intercourse with a pregnant woman [when getting married to her] until she gives birth to her child." [Abu Daawood]

2)     When this woman gives birth to her child, the child is considered as being born out of an illegal sexual relationship so he has to be named after his mother. It is not permissible for you to name him after you as adoption is forbidden in Islam.

3)     You have to conceal the sin of this woman, so you should not inform anyone that she committed fornication or that she is pregnant, except her husband. It is an obligation to inform the latter, because there is some religious harm in concealing her sin from him, which is that he might have sexual intercourse with her while she is pregnant and this is forbidden; in addition to this, it could be that he would name the child after him but he is not the father.

4)     It is not permissible for you to marry her since she is married, but if her husband divorces her or dies, then it is permissible for you to get married to her after the end of the waiting period provided she has repented from her sin.

Allaah knows best.