FAIRFAX, Va. -- Actor Amber Heard is expected to take the stand in her own defense Wednesday in a civil suit filed by her ex-husband, Johnny Depp.Heard's anticipated testimony comes after a psychologist hired by her lawyers testified that Heard suffers from post-traumatic stress disorder from multiple acts of abuse, including sexual violence, inflicted on her by Depp.Depp is suing Heard for libel in Fairfax County Circuit Court after she wrote a December 2018 op-ed in The Washington Post describing herself as “a public figure representing domestic abuse.” The article never mentions Depp by name, but Depp’s lawyers say he was defamed nevertheless because it clearly referred to accusations she made in 2016 during their divorce proceedings.Depp spent four days on the stand earlier in the trial, testifying he never struck Heard and that he was the abuse victim.