Pullen was last seen in her hometown of South Bend, Indiana on December 31, 1986. Her hairdresser saw her at a Save Mart store on U. S. 33 and Bell Road during the day. Pullen told her hairdresser that she planned to have a New Year's Eve party at her home later that evening. It has been established that Pullen returned to her residence in the Windward Village Mobile Home Park on South 13th Street near Niles, Michigan sometime later in the day. She has never been seen again.

Authorities checked Pullen's trailer on January 12, 1987 after she failed to pay the rental fees for her mobile home lots in the park, and her relatives called the police to say they had not seen or heard from her in nearly two weeks. Investigators discovered a half-eaten sandwich and a cigarette which had burned down to its filter in an ashtray inside Pullen's home, where she lived alone. The sandwich was spoiled. The television in the mobile home was turned on. There were no indications that a struggle had taken place and authorities believe Pullen left the residence in a hurry but willingly, intending to come back shortly. All her personal belongings, including her clothing, her luggage and her vehicle, were left behind.

There were no other leads in Pullen's case until the early 1990s, when one of her neighbors told authorities that she had witnessed Pullen arguing with two men outside of her mobile home on December 31, 1986, the date she was last seen. One of the men was identified as a former tenant of Pullen's. He leased one of her trailer lots, but there is no record of him paying any rent. The man was questioned by investigators and claimed he did not see Pullen the day she vanished. He also stated that Pullen paid him for work he did for her prior to her disappearance. Pullen's final check to the tenant was dated December 30, 1986 and was for $500. The man claimed that the check was a holiday gift for himself and his family.

It was discovered that the same tenant had used Pullen's Discover credit card twice after her 1986 disappearance; once on January 11, 1987 and again on January 16. Both times it was used to purchase items at the Highland Appliance store in Mishawaka, Indiana. The man stated he had Pullen's permission to use the card to charge household expenses, which totaled more than $1,000 on her account. He also claimed he did not know Pullen was missing at the time he used her credit card, and that she had written several checks to him in compensation for work he did for her. Pullen's diary entries, however, indicated that the man was extorting money from her.

Pullen formerly worked at the Simplicity Pattern Co.. She lived with her husband on a farm in the Niles, Indiana area until he died, then she moved several times before coming to live at Windward Village. She was estranged from her relatives at the time she went missing. No one has been charged in connection with Pullen's disappearance, but it is considered very suspicious and foul play is suspected. Pullen has not used her Social Security number since her disappearance; neither has she made an insurance claim for her insulin.

Pullen's case was reopened in 2008 and investigators stated they had a good chance of solving it and had several persons of interest in mind. Police are investigating her case as a homicide.

Some agencies state that Pullen was 71 years old at the time of her disappearance.