The older we get, the more people we know pass away, until our owm time has come.
Of course you are sad when a loved one gets ill or passes away, that´s normal.
It is also normal that one has difficult to see possitive things when living in a dark period of live.
Of course you are mourning, of course you feel sad and of course you worry, but your first responsibility is your own live. You have a choice. You can sit down, feel sorry for yourself, maybe grab some bottles of whiskey and destroy your live (you wouldn´t be the first one).
Or you can learn from this.......live is too short. When your health and finances permit, do the things which make you happy, do the things you want to do before it´s too late.

As I said, it is difficult to be possitive when one has a bad time and it is normal to worry. And I am aware of it is easy talking for me, not being in your situation, but I can not agree with those worries your wrote down.
How terrible for those people living in a warzone, it is not your war, it is not your problem and it won´t affect your life, except for everything to get more expensive.
Climate change is a natural thing, has happend many times in earths history and nothing we can do about. For some millions of years ago sealevel was 50 feet higher then now, iceages has come and gone. We are now living at the end of a iceage so the earth is getting warmer and sealevel rises again. Quite normal for the planet but not what humans are used to because we humans only excist for such a short time.
Economy yes, we have to try to live a good life with the amount of money we have.

Wishing you all the strenght to make the right choice, I think it´s best to stop following the (western) news and go out on a ride, a walk in nature or do whatever interests you may have, preferably outside the house.