could be a word like recluse, solitary, anchorite, eremite, loner, monk, anchoress, isolate, stylite, ascetic, misanthrope, solitaire.
or there are words like unaccompanied, alone, lone, solo, single, solitary, unattended, single-handed, unescorted, by oneself, companionless, lonely, lonesome, partnerless
