This question probably belongs in IMHO because we can’t provide any REAL answers.
Is she dead? Yes. From long experience, homicide detectives know that if you find personal effects like a purse (with all identification), her car, but no body, and no ransom demand, the victim is dead in all probability.
Was it Condit? It’s doubtful hthat he personally took her life, but hard to believe he wasn’t involved in some way. Most murders are committed by someone close to the victim.
Suicide? Highly unlikely. Most suicides are committed at home, or barring that, a public park. In a highly populated area, it wouldn’t take long for a corpse to be found especially with the spate of hot weather. Most suicide victims want to be found. There aren’t any bridges in D.C. high enough for suicide, either.
Somebody else? A random attack by a stranger is far out, but not impossible. Again, most violent personal crimes are committed by someone personally known to the victim.
Is she alive? Nope.
Is she in hiding? Nope. By all accounts she had a good relationship with her parents and would have contacted them or one of her friends to let them know she was okay - as most people would.
Was she kidnapped? Considering she didn’t drive herself to the crime scene, didn’t take her purse, and no blood was found in her apartment, the logical assumption is that she was taken. That’s kidnapping by anyone’s definition.
It’s not illegal to disappear unless you’re avoiding some legal responsibility, like a court date, or attempting to defraud someone. When an adult is missing, there’s very little the police can do unless foul play is suspected. At this point, considering all the media coverage, if Chandra were alive and watching on TV, she would be guilty of hindering a police investigation and withholding evidence (i.e. herself).