Having a life is the state of not just being alive but doing something meaningful with it. Often used to insult people who don't have a life like johny.
"Jimmy tried to find the definition of having a life on urban dictionary but there was none he wrote a definition that he thinks is funny" said Johny "HA HA jimmy doesn't have a life"
A polite way to tell someone to fuck off and die because that person has created the circumstance between you and them which makes you care less if you ever see them again.
He could not deal with her bullshit and destructiveness in their relationship, so he signed the letter "have a nice life."
By Danika
Have A Good Life
1. A final phrase used when you are departing paths from an individual that you will never see ever again in your life or theirs.
2. A casual and polite phrase used to express well-wishing for an individual's prospects and life in the period of time that you will not see them. Could be a day, could be a year, could be never again. There is no way to be sure.
Intern: I just finished my internship and wanted to thank you all for supporting me. I hope to be back next year :)
Co-worker: Thanks to you too! It was fun. Have a good life! Bye.