In which occasions I use 'lonesome' and 'lonesome' is similar to lonely?

[javivaso]

Synonym Search, Intermediate level

ESL/EFL Test #114 "Synonyms for solitary and single", question 5

After his mother's death Peter used to spend long ......... hours at the bar.

(a) single
(b) solitary
(c) alone
(d) lonesome

Synonym Search, Intermediate level

ESL/EFL Test #114 "Synonyms for solitary and single", answer 5

After his mother's death Peter used to spend long lonesome hours at the bar.

Correct answer: (d) lonesome
_________________________

in which occasions I use "lonesome" and lonesome is similar to lonely?

javivaso

[Conchita]

Perhaps these threads might shed a bit of light:

Solitary vs lonely

Lonesome vs single

Alone vs lonely