Conditions for the validity of Nikaah

Nikaah without witnesses

Q: If a boy texts message a girl saying, "Do you accept me in nikkah" and the girl texts back,"yes" and then the boy texts, "same here", and during this there is no witness on the girl's side but the girl does not know if there were witnesses on the boy's side or not. Is the nikaah valid?

Nikaah after divorce

Q: I am divorced and have two children. I had a court marriage in Pakistan but the nikah is not registered online. My husband told me not to tell the imam I am divorced because I didn’t have divorce papers and they needed proof. So I didn’t tell the imam I’m divorced and he wrote that I am a virgin on the papers. Is the nikah valid? I am from UK and my husband is in Pakistan.

Making Allah Ta'ala a witness in a nikaah

Q: While getting married to someone you need at least two witnesses one male and two females or two males and one female. What if someone gets married in secret without telling anyone and they make Allah their witness and say qabul?

I read somewhere that if a mature girl and boy says qabul with the intention of making her/him their spouses, they'll eventually become husband and wife in the eyes of Allah. Is it true?

One of my cousins secretly went into a relationship and she considers that guy as her husband. He also considers her as his wife. So with a pure heart are they married in the eyes of Allah?

Nikaah without witnesses

Q: I did ijab o qbul without mehar and wali and without witness 8 years ago. There was no physical relation but I realized it is wrong. I left that boy now and my father is getting me married to my cousin. Should I get married to him or tell my father about the nikah 8 years ago?