a cappella
alone
isolated
lone
lonely
marooned
separate
solitary
solo
stranded
tod
unattended
alienated
aloof
apart
companionless
detached
friendless
homeless
insular
isolate
kithless
lonesome
removed
rootless
separated
single-handed
stag
unabetted
unaided
unassisted
unchaperoned
unescorted
unseconded
unsupported
withdrawn
unmolested
accompanied