The trouble isn't whether you trust HER memory or not. It's everyone's. I just watched an episode of Brain Games the other day, where a mugging was staged as 20 or so people were gathered around a 3 card monte game. Interviewed within minutes of the mugging, and people were SURE they were right, but they were so wrong that they didn't even know how many people were involved, whether they were male or female, and in one instance, a witness actually thought the mugger was the one being robbed.
Yet they were all pretty darn sure they remembered the events correctly. Now, you extrapolate that over the course of YEARS, and details get lost, others get added, and we can only be sure of one thing-that most likely her story as told to you is not the same thing that actually happened.
Another failure of memory I saw involved a group of people writing down their memories of where they were and what they were doing during the attacks on 9/11. They did this within a week of the attacks, and the memory was fresh. I think it was 7 years later, they were brought back to recall again where they had been and what they were doing, and over 60% of the people didn't just lose details, they had added in a bunch of new ones.
And that's for something big and traumatic, that you think you'd remember. Also, they wrote it down which helps establish a memory too.
There's a reason skeptics are quick to point out the fallacy of memory-because it's been proven to be true over and over again. Heck, look at my post. I'm having a hard time remembering the details of the programs I watched. I saw the Brain Games episode probably all of 2 weeks ago. It had my full attention, as I really enjoy the show.