The best replacement for alone is lonely.

The best alternatives to alone are rated as following:
★★★★★  lonely
★★  along
★  in pairs
★  together
★  by myself
★  with friends
★  loneliness
★  roommate
★  not alone
★  living with parents
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  being lonely
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  solitude
  in a group
  overly attached girlfriend
  web based
  walking with friends
  with roommates
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  with others
  let alone
  as a team
  pairs
  die hard
  studying in groups
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  with family
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  in group
  lonely difference

Your alternative for alone is not listed? Suggest!
Speaking about alone, one probably shouldn't forget about being lonely.

Other search terms related to alone and their ratings are:
★★★★★ being lonely
★ alone
You have in mind a companion for alone and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of alone in all years. Click on graph for more.
alone
lonely
along