The quote “I used to think the worst thing in life was to end up all alone. It’s not. The worst thing in life is ending up with people who make you feel all alone” originated with Robin Williams.
An image graphic featuring a photograph of Robin Williams and a quote ostensibly uttered by him is frequently shared on social media:

The quote reads: “I used to think that the worst thing in life was to end up alone. It’s not. The worst thing in life is to end up with people who make you feel all alone.”
While Williams has a connection to this quote, he is not its original author. This quote comes from the 2009 film “World’s Greatest Dad” that was written and directed by Bobcat Goldthwait.