Comments or Likes made on Public posts are themselves “public”. Facebook is testing a feature to allow individual comments to be restricted to your own Friends, and not shared publicly.
Facebook is also testing a feature whereby Friend requests will automatically expire after 14 days. Most of the friend requests I had received were odd or just spam – from people I do not know, in far off countries, having no common interests.
Your best bet is to wean yourself off Facebook and deactivate or delete your account, if you can.