I now consider this somewhat debunked. Ill keep this here for historical reasons.
Factor that probably disproves the theory that explains why she left campus.
James Renner interviewed Mauras fellow nursing students here:
This is the best and most detailed evidence I have. And I have to admit it debunks what I have supposed about her transportation needs to stay in the nursing program.
The key part is that the clinical groups were 6 -8 students. If that's the case, then it is highly unlikely Maura needed reliable transportation to stay in the program. What is the chance that at least one of 6 -8 students would have a car to take the others in. Its almost certain someone would have a car in this case.
Ok. So until I have better information, I'm going to say this line of arguement doesn't work in as much that it attempts to explain why she left campus. On the other hand, i still think there is an unanswered question: Why the change of behavior towards the car?
Also - the idea below - seems to erroneously assume that no other transportation solution could be available to Maura that particular week. Certainly - a lack of reliable transportation is more of a long term issue - only that things might not work out one week in the future. But realistically - it does seem that some sort of short term solution could have probably been found.
So I'm not so sure that a better explanation of her leaving - if there is one - has been articulated above.
Historical post below...
I believe the death in the family excuse was an attempt to buy time until she had a new car for her nursing clinicals.
At the time of her disappearance, Umass Amherst's absence policy was that there were no excused absences for nursing students, except for a death in the family. Although I have seen the policy, I can't find it now.
Since the only way she could get an excused absence was by claiming there was a death in the family, she emailed her professors to assert the claim.
Fred Murray seems to agree that the death in the family claim was to get an excused absence. He says so here at 1:07: http://www.wcvb.com/chronicle/missing-segment-two/24486306
I believe that she placed her plan into action as soon as she realized that she would not have reliable transportation to clinicals as required. I believe she would have realized this after her dad dropped her off on Sunday, without obtaining a replacement vehicle.
From the Caledonian Record of February 13, 2004, linked here:
(Presumably regarding acquiring a replacement car)
"Maura, this is me .. like always We will solve this" "I don't know exactly what you think is the matter..." Murray said. again, pleading to his daughter, "It isn't anything that can't be easily solved."
Sharon Rausch said, on page 6, here: http://docslide.us/documents/maura-is-missing-a-special-report.html
"Maura must have packed her college textbooks as well since they were later found in her car. Maura had been getting rides from friends at school due to her car problems, says Sharon Rausch, so it is unlikely the textbooks would have already been in the car."
I believe Maura felt that she should not be seen on campus for a week, and therefore had to go away somewhere she could study during her absence.
I believe Maura decided to to go to her favorite place to study in lieu of attending classes, and have a little fun on the side.