What do mean by loneliness?

Loneliness is the unhappiness that is felt by someone because they do not have any friends or do not have anyone to talk to.

Loneliness is a state of mind linked to wanting human contact but feeling alone. People can be alone and not feel lonely, or they can have contact with people and still experience feelings of isolation.

“Loneliness is not necessarily about being alone. Instead, “it is the perception of being alone and isolated that matters most” and is “a state of mind”. “Inability to find meaning in one's life”, “Feeling of negative and unpleasant” and “A subjective, negative feeling related to the deficient social relations” “A feeling of disconnectedness or isolation.”

#hope it helps

may i see the historical information and the excerpt?

it would be d because the however is more proper and the comma is placed in the right spot