Mahendra said that he doesn't need time, as his mind is clear, still Anu tells him to think about this, Mahendra to be honest already thought about this. He sees the tragedy of his father, even having two children he doesn't assure his good life. Your good karma is your only assurance, he is rich and he can take care of Anu until old age, and with money, they can hire someone to take care of them in their old age.
He can also see Chinu's love for Anu, and there are many children in the world, who don't have parents, they will adopt them, he even if Anu can convince the child, not wanted to risk her life again.
He already feels fear of losing her, he doesn't want to face that again. So what he is going to tell her is quite fixed.
