FORT LAUDERDALE, Fla. — The mother of a teenager who says he had a sexual relationship with his teacher broke down on the witness stand Wednesday, saying she felt betrayed by a woman she considered her best friend.

Grisel Vaden, 39, testified that she was dumbfounded when her eldest son Donald Vaden, now 19, came to her one Saturday in June 1999 and confided, in crude terms, his true relationship with his former middle school teacher, Beth Friedman. Friedman is now on trial for statutory rape, a felony charge that grew out of what Vaden testified her son told her on June 12, 1999.

"Donny said, 'I don't who I am anymore. I don't know what to do,'" Grisel Vaden told a hushed courtroom in Broward County Circuit Court. "He said, 'I've been f***ing Beth.'"

Donald Vaden, the alleged victim

Prosecutor Stacey Honowitz called Grisel Vaden to the witness stand as the first of a series of prosecution witnesses she hopes will corroborate what Donald Vaden has already told the jury. Although her dates and details did not jive perfectly with her son's, Grisel Vaden essentially confirmed for Honowitz that she saw Donald Vaden with jewelry, a car and other gifts the prosecution claims came from Friedman.

Grisel Vaden said she had trouble believing her son about the relationship. Friedman, who is now 42, had let the Vadens and Grisel Vaden's boyfriend live in her condominium with her for about nine months and appeared to treat Donald Vaden like a nephew, Grisel Vaden testified.

"I said, 'No way!'" Grisel Vaden said. "I was in shock. I didn't know what to say. Nothing came out of my mouth. I was numb."

Over Donald Vaden's objections, Grisel Vaden and her ex-husband, James Vaden, filed a complaint with Hollywood police the following day. Among many things, she told a detective that Donald Vaden confided that Beth Friedman offered him $25,000 to impregnate her.

Friedman, who pleaded not guilty to charges that could bring 76 years in prison, denies she ever had a sexual relationship with Donald Vaden, who was 15 at the time the affair allegedly began. He has already testified that he was a willing participant in the alleged relationship and did not want to see his former lover get into trouble.

Grisel Vaden, the only witness to testify Wednesday, told the jury that she did not suspect anything inappropriate between Friedman and her son because she considered Friedman almost like family. Friedman had Thanksgiving with the Vadens in 1997 and often took Donald and his younger brother, Darius, to movies, arcades and amusement parks, according to Donald and Grisel Vaden's testimony.

At first, Friedman would just visit the Vaden home and play board games with Grisel, Donald and other family members. When a problem with a neighbor developed in 1998, Grisel Vaden testified, the Vadens moved in with Friedman in her condominium and paid $300 a month in rent, all utilities and food costs.

Donald Vaden and Friedman would often "tease" each other by squirting each other with water pistols and making sexual remarks, Grisel Vaden said. One time, she said, Donald Vaden said in crude words that Friedman did not know how to perform oral sex properly. Friedman replied that the teen had a small penis, Grisel Vaden told the jury.

Mother did not suspect

Despite such frank talk, Grisel Vaden said she was not suspicious of a sexual relationship because she trusted Friedman. Vaden said she never noticed anything out of place until after they moved out of Friedman's home in April 1999. Friedman's condo association was complaining that two families were living under one roof, the witness explained. After moving out, Grisel Vaden used her key to enter the condominium in late April 1999 and found that Friedman had redone her master bedroom to include a white leather couch and other furniture that suggested it was not Friedman's bedroom, Vaden said.

In the closet were Donald Vaden's clothes. In a drawer she discovered marijuana, drug paraphernalia and what she believed to be cocaine, she testified. Grisel Vaden said she was furious and confronted her son and Friedman.

"I told her I had seen what was in the drawer in the master bedroom and I didn't want Donny at her house, and he was not allowed to be at her home anymore," Grisel Vaden testified. "She just hung up on me."

Donald Vaden started sneaking out to see Friedman after that, his mother said. But she still did not suspect sex.

"I was not suspicious because she was my friend, and was a teacher. She came from a very good background," Grisel Vaden said, beginning to cry. "There is no way I ever could have imagined ... She's my age, actually a couple of years older."

Defense: Vaden thought son was lying

During his cross-examination, Friedman's lawyer, David Bogenschutz, quickly tried to establish that even Grisel Vaden found her son's claims that he was sleeping with the teacher too absurd to take seriously. Bogenschutz noted that Donald Vaden made comments on several occasions that would have set off alarms for most parents.

Bogenschutz pointed out that in a deposition Grisel Vaden had said that her son had told her several months before she went to police in June 1999 that Friedman had offered Donald Vaden $25,000 to get her pregnant.

"In fact, [the comment] was made April 24th and you just blew it off because he was joking, didn't you?" Bogenschutz said.

"That could have happened," the witness conceded.

"Now you say you believe him?" Bogenschutz asked.

"She was my friend," Grisel Vaden said, leaning forward in her seat and raising her voice. "She was supposed to be taking care of my child, not screwing my child and offering my child $25,000."

Pressed on what she believed and when she believed it, Vaden said it was not until her son came to her in June 1999 appearing confused and anxious that she really considered the possibility that he was having a sexual relationship with Vaden. This testimony could prove important to the defense, which contends that Donald Vaden is a lying, drug-abusing thief who concocted the story because he likes to brag.

Grisel Vaden is expected to be back on the stand when the trial resumes Friday.