My Grandmother Dorothy Ann Delaney (GUEST) went missing in January of 1965.

Her last known address was in Gilbertsville Mass.

I am trying to find out what happened to her.
I have her date of birth and that is about it.

There was a file opened on her as a missing person by her brother inlaw who was at the time a On the Police force in a local town. Also there was some FBI envolvement.

There is speculation that she may have had a bad ending.

Where should i begin in trying to locate her or her burial spot ?

Thank you