Birmingham, Ala (WIAT)  Joran van der Sloot's self styled "guardian angel" says she's "resigning" from her advocacy of the convicted killer's cause saying she's broke, exhausted and discriminated against by both the Peruvian and American governments.

Dr. Mary Hamer, a Florida radiologist with Alabama roots, has not only been an outspoken advocate for van der Sloot, she says she has spent more than $100,000 on his legal defense and is now poor.

In a letter sent to, among others, President Obama, Joran van der Sloot and the Holloway and Flores families, Hamer says " "The U.S government & the Peruvian governments, Beth Holloway, the Flores family, Anita Van der Sloot & Joran have won & I lose. I accept defeat."

Hamer came into the picture after van der Sloot was arrested for killing Peruvian student Stephany Flores.   Flores' body was found in the Dutchman's Lima hotel room five years to the day that Natalee Holloway walked out of an Aruban bar with van der Sloot and vanished.  Although van der Sloot is still considered the prime suspect in the Holloway disappearance, he was never charged by Aruban authorities.

He confessed to Peruvian investigators that he killed Flores when she found material relating to Natalee on his laptop.  He was sentenced to 28 years in prison for that killing just a few weeks ago.

Van der Sloot has begged Hamer to keep supporting him, particularly financially as he appeals his sentence.  Her letter seems to cut that cord.