Making sajdah-e-sahw after salaah

Q: Is it right to perform sajda-e-sahw if someone forgets to make it within salaah? When I remember, without reciting anything else, I just to sit down and recite attahiyyaat upto (abduhu warasuluh) then one salam on the right side then two sajdahs of sahw and then attahiyyaat, durood and dua and then 2 salaam. 

Masturbating while fasting

Q:

1. When i was a young unmarried girl, I used to masturbate reaching orgasm using water on my clitoris. At that time I did not know that ghusal had to be taken and usually just had a normal bath (not fulfilling the fardh of ghusul). What is the condition of all my fast and salaah for those years?

2 When I got married, I remember my husband made me reach orgasm through clitoral stimulation while I was fasting in the month of Ramadaan. I was immature and naive and unfortunately not aware of the mas'ala. Years have passed but it keeps troubling me as to what is the conditon of all my salaah and my Ramadaan fast. Please advise

Divorcing one's wife due to being unable to satisfy her

Q: I am a 33 year old married man. I am really confused regarding my problem. I love my wife but I am not able to please her and give her a happy life.

Its been 3 years since our marriage. She was married to me with a lot of expectations to have a beautiful married life. After many treatments, my problem is still not solved. I am not able to satisfy my wife sexualy. I have premature ejaculation.

Moreover I have nil sperm count due to that she is not getting pregnant. The doctor said that I dont have the ability to make a woman pregnant. We can only try IVF.

We tried to perform by giving her oral pleasure and forplay and after she finish, I thurst. Its always makes our relationship more complicated.

I want to make her happy but if I am still like this she would never be. I feel that it would be better to divorce her so that inshallah she can get married to another man and have a better life.

Should I divorce her or should we keep living with the same issues?

Touching one's sister with lust

Q: If someone touched his own married or unmarried sister with lust, will this nullify his sister's marriage?

If she is unmarried at that time (when the incident happened), will her marriage be valid in future? What is the ruling if she is married at that time (when the incident happened), will this nullify her marriage?

Mother telling the son to never remarry

Q: If a man got married and his mum told him that he must not marry again and he's been through hell in his marriage. His mum is late now amd his kids are grown up and working. He found somebody in his life who is going through as much as him. She was an orphan and now he wants to know if he can marry this woman despite what his late mum said. He is only living in the house because of his kids. Can you advise if he can marry and be happy again?

Stressing before an interview

Q: I feel like I am in a great trouble because I have to face an interview just after 1 month. I can't remember things, I forget things. My mind is not focused at all. I am worried weather I will be able to answer the questions of the interviewer or not.

Please help me in the light of Islam. What should I do?