Since the light or em radiation from objects we now access is supposedly what happened many many years ago...could it be possible that those objects no longer exist at this very moment?
Absolutely. And how is it possible that we are viewing events that happened billions of years ago at at the beginning of the universe yet it is impossible for matter to travel fast enough to be that far away in lightyears according to special relativity?
Not only possible, but quite likely in many cases. What we see as dying stars that are 150 million miles away are almost surely fully dead by now.
Yes. Today if we see a supernova 12 billion light years away, it surely is no longer either a star or a supernova. The nebula has dissipated and the core has probably become a neutron star after passing through its pulsar phase. Yes, I would even go so far as to say that not many large scale objects we see far out (billions of light years) in space are still what they appear to be, red dwarfs, galaxies and supermassive black holes excepted, even if we hypothetically could see everything that’s out there that far out.
Of course. It’s also possible the universe has already collapsed and we’re seeing only what used to be. There is nothing to prevent our obliteration; that it hasn’t happened yet is so far, so good, but no guarantee it won’t happen before you finish reading this.