all by lonesome
all by (one's) lonesome
Completely alone. My roommate left town for the weekend, so I'm here all by my lonesome.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
all by one's lonesome
Rur. all alone; by oneself. Mary's folks went out and left her all by her lonesome.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.