Grief and loss are simply inevitable as long as one exists here, but anyway we all have to die and lose everything someday, eventually we very likely won’t even exist in the memories of those who continue to exist here. And anyway whatever happens in this world after we are gone could never be our concern as we simply won’t exist, in death everything is forgotten about for us.
You say "we all have to die and lose everything someday". From my perspective, everything is not much to lose. I can't recall a happy moment for years. Every day is like ground hog day. I hate to wake up and have to think about my life, which is a daily struggle. Waking up and getting out of bed is actually my biggest daily struggle. My only enjoyment comes from some nice dreams that I sometimes have.
This is not living and there is absolutely nothing to lose. Do I live, or merely exist, is the question. Am I indistinguishable from the meat that most of us consume every day? In actual fact, the people of this forum who are contemplating ctb are more enlightened than the average person who tries to ignore the fact that they will pass away sooner or later.
An interesting concept about time when you're gone. The second you pass away, the whole world has died. All your friends and family (if you have any) passed away in the same instant. The dust we leave behind has no concept of time and a second equals a million years, or infinitely. In fact, the world doesn't exist when you lose consciousness as the whole world only existed in your consciousness.
Now if you believe in the Biblical afterlife, the second you pass away you will be resurrected along with the billions who passed away over the world's history and time yet to pass. Each religion will have its own thoughts about this and what comes next.