Absentia (2011) on Netflix

Plot summary

Tricia lives alone in a Glendale, California, neighborhood, pregnant, and after seven years without her husband Daniel she is ready to have him declared dead in absentia. Her younger sister Callie, who is recovering from addiction, moves in and helps with the death certificate paperwork and the search for a new apartment. Tricia keeps having nightmares and hallucinations of Daniel, which her psychiatrist reads as stress and guilt. While out jogging, Callie encounters a gaunt man in a tunnel who is shocked that she can see him; he says his name is Walter Lambert and asks her to contact his son. She returns with food and finds the tunnel empty.