How do you guys cope with the death of your pet?

Right now my cat has been sick, totally sick. Both my father and brother have been talking like my cat is dead, which is not true. I keep trying to heal him, put medicine on him, feed him—just everything—but every second, every minute, both of them keep saying he is dead, which is making me too anxious, and I can't cope with it because I know myself he is hurt and old; he already watched me through pre school to me graduating. I just can't think the worst ending and I hate it.

He's malnourished due to not eating too much, hes hurt, and no, I can't go to the vet; we are not rich.