Taubah and Repentance

Q: If someone has done repeatative sins and he is unable to repent and is feeling Allah's anger on him, what should he do?

Q: Will Allah forgive a murderer or rapist if he repented and the victim also forgave him? Will Shariah still punish him if no one knows about it? Will Allah punish him in the hereafter on the day of Qiyamat because he did not get punishment in this duniya and just repented to Allah, and the victim also forgave him?

Q: Can one ask for forgiveness from another human on the day of Mahshar if he could not do it in his life time in this world? 

Q: I accidentally saw somebody in my family naked. Is it a major sin?

Q: What are the virtues for one who gives up sin for Allah's pleasure?

Q: I have a sin that troubles me alot like when I think of it my heart feels heavy. I have made tawbah and made a firm intention in my heart to never resort back to that sin. I'd like to know what's the signs of an accepted taubah?

Q: Should one ask forgiveness for a sin if one is unsure whether one has committed the sin at all?

Q: If someone repented from a sin, and then in the future was thinking about the sin they committed and took pleasure in the enjoyment if the sin they once committed, do they have to repent once again?

Q: I heard that if someone does zina and asks Allah Ta'ala for forgiveness, Allah Ta'ala forgives that person but that person wouldn’t be allowed to see Allah Ta'ala in Jannah? Is it authentic?

Q: I have committed sins that I am not proud of that nobody knows. I try to forget them but I can't. What should I do?