Let me tell you something man, even though I am currently a resident in critical care and see this stuff everyday, sometimes 16 hours a day or more, nothing will ever prepare you for having your own family member being critically ill.
My dad became sick two years ago. He had cholecystitis, sepsis, bi-lateral lung pneumonia with two separate bacterias, two heart attacks, dehydration, kidney failure, developed an abscess in his small intestine. . He had naso-gastric tubes, t-tubes, incubated on a ventilator, Jackson-prat drainage tube for the abscess, central line in his neck and femoral line to run fluids and antibiotics.
I see this shit everyday and I broke down crying because seeing my father like this was horrible and I couldn't even think.
They tried weaning him off the ventilator after three days and he didn't respond too good. The next day I got a call from the attending (also a close friend of mine) that he pulled his own endotracheal tube out and was breathing fine on his own. He recovered after a month in the hospital but man was it a rough road.
I know it hard to see all of the tubes, wires, etc but it is only helping him in the long run. Even though he is on a ventilator, that doesn't necessarily mean he can't breathe completely on his own, just that he needs more oxygen than what he can take in right now with his decreased heart function.
I give you my best and I know it is hard for you man, but try to hang in there.
I have seen a lot of things happen in critical care and even us as medical professionals felt like their wasn't anything else we could do. But in the end it worked out fine in a lot of cases.
God bless.