The high school cheerleader who allegedly hid the stolen handgun used to kill actress Nicole duFresne never should have covered up for the murderer, the actress' heartbroken fiancé said yesterday. "She didn't have to flee the state, hide the gun and take on another person's crime in the way that she did," 29-year-old Jeffrey Sparks said of Ashley Evans, who went to her father's Maryland home after the crime. "She could have come forward. She didn't have to hide out," Sparks said before a memorial ceremony on the lower East Side to honor the woman he had planned to marry...