SAN DIEGO, Aug. 31 — Charles Manson “family” members Susan Murphy and Lynette “Squeaky” Fromme are practically roommates again.

Miss Murphy, 34, and fellow inmate Diane Ellis, 33, captured in Oregon last week after escaping from Terminal Island federal prison in Los Angeles, have been imprisoned in the Metropolitan Correctional Center, a year-old prison that is considered escape-proof.

Miss Fromme, 27, is serving a life sentence here for attempting to assassinate President Ford last year. Miss Fromme and Miss Murphy were roommates in Sacramento, Calif., at the time of Miss Fromme’s arrest.

Miss Murphy had been held in Ins Angeles for conspiracy to send threatening letters to businessmen she accused of polluting the environment. Miss Ellis was jailed on a parole violation after being convicted of bank robbery.