Mark Robins is the protagonist and first-person narrator of On My Own. He moves into the Trailer Park as a result of separation from his wife, Judy Robins.

He has a son Gene Robins, 44 years old at the start of the novel, and a daughter Jeanie Robins, 20. He also has three grandchildren: 12, 8 and 6 years old.

He gets into a relationship with Caroline who also lives at the Trailer Park.