You don't to have worry about everything; be selective. Not worrying about things in the world is not where I'm at, but I'm careful to diversely mix my online subjects, so that I don't get stuck in a mental rut focusing on one thing. For instance, I'll read heavy stuff like Ukraine and Palestine, but I'll mix that with the antics of domestic parrots on FB or YT. This seems to keep me quite level as it seems one can overthink things and end up disturbed.
My worldview is to accept that good and adverse things happen simultaneously everywhere. It is up to me which I choose to see. Self-censorship is a useful skill at the appropriate time.
The pursuit and feeling of constant happiness is not sustainable physically... your happy hormones are not meant to be on constantly. I always crash mentally after a period of solid happiness
I think pursuing peace of mind is the nearest to a positive sustainable physical/emotional state because it means you have balance in your activities and thinking.