Yes, she could. But if that is so then it is a therapy issue. If she is suppressing further crimes, then she may remember with therapy and it can be dealt with in a safe atmosphere.
But if she is denying it to LE, then it is possible that it stopped. And if it did stop, then how hurtful would it be when everybody believed that she was lying and that it didn't stop like she said? Would she feel like people were calling her a liar? Would she feel like everybody wanted to sensationalize her life? After all she is the one who lived it and knows what happened. Would she feel mimimalized because people didn't feel her story was bad enough when she told the truth, and that people had to make it more sensational than it was?
I understand as to what you are trying to say, but if it is possible for Garrido to get any benefits from claiming there was no sex for years (at trial), I would be less inclined to believe these claims. If it wouldn't make any difference, I would be more inclined to believe these claims.