MySQL: Join one Row in a table with two Rows in other table
Perhaps I'm misunderstanding your request, but based on the text in your question that sounds simple enough:

SELECT
    U.first_name AS "User Name",
    U.email_id AS "User E-Mail Address",
    BossUser.first_name AS "Authorizing User Name"
    BossUser.email_id AS "Authorizing User E-Mail Address"
FROM
    user_login AS UL
    INNER JOIN users AS U ON UL.user_id = U.user_id
    LEFT JOIN  user_login AS BossLogin ON U.created_by = BossLogin.user_name
    LEFT JOIN  users AS BossUser ON BossLogin.user_id = BossUser.user_id


This allows for users without a created_by; if that field is NOT NULL, you can replace the LEFT JOINs with INNER JOIN.