Why is there so much bickering in this thread? It won't help the family, won't catch any possible perpetrator(s), and won't make a single difference in whatever happened to Maura.
It might even turn away someone who really could have offered something important, or who was involved in some way and stumbled upon this site.
Okay, now that I've said that, I'll add the actual input I came here to post...
I, personally, believe that, since Maura(allegedly) ran off after the final car wreck, the lack of footprints suggests that she did get into someone else's vehicle and leave the scene that way(she may have initially planned to go someplace on her own, on foot - but, a few too many minutes spent outside in the elements might have changed her perspective on that idea).
There is no proof that she planned to commit suicide - her behavior in the days leading up to her trip suggests sheer, if oddly well-planned, recklessness(in other words, the mindset of, "I like to make sound decisions, but I must get out of here as quickly as possible before I snap!"). Plenty of people have contradictory impulses like that every day, without the slightest desire to off themselves. Stress can get so unbearable that even the most stable people can lose all ability to plan for a more convenient time, or to wait for a more reliable car, or to establish a better financial state(or to rely any longer on others they may feel unhappy with or overly dependent on).
Furthermore, the fact(or, again, the alleged fact) that she initially left the scene on foot after her wreck demonstrates self-preservation(as does taking her "getaway trip" in the first place, really)...who cares if you could be facing a DUI if you don't plan on being around long enough to suffer any of the consequences it would bring to you?
If she wasn't abducted, however, it does seem like suicide IS the only other viable explanation...even if the map shows it to be physically impossible for her to get to a good enough "hiding place" in such weather before succumbing to natural forces like hypothermia(and being quickly found, out in the open).
I'd say it's a 98% likelihood that she had help to leave the scene(whether it was help she wanted or not...hopefully whoever took her was friendly and did no harm).