"I just kept cutting her. No one could stop me. I was doing the work of God," he told the paper.
Brea's relatives issued a statement on Friday expressing support for the actor, describing him as "a compassionate, gentle, intelligent, spiritual and loving man."
Yanick Brea, 55, had cuts to her head when she was found Tuesday in the bathroom of her Brooklyn apartment, police said.
Brea, who had small roles in ABC's now-canceled show "Ugly Betty" and the movie "Step Up 3D," was in the bedroom with a 3-foot-long sword, police said.
The actor is facing second degree murder charges in New York and is now under psychiatric evaluation.
The Associated Press contributed to this report.