What is the difference between these sentences below in terms of meaning?
He lives by himself.
He lives on his own
If you ask me, the first sentence connotes that he doesn't have a housemate/wife, like being alone at home .The second sentence connotes that he doesn't have girlfriend/boyfriend or friends/family who support him when he needs, like feeling lonely.
Best Answer
They can be somewhat interchanged; that is, they have similar meanings that in some contexts are equivalent, but in others they have a different connotation.
"living by himself" tends towards meaning without anyone in the same house.
"living on his own" tends towards meaning without requiring support.
These examples show where one phrase works but the other doesn't.