First, false memories are an entirely possible and established phenomenon. Suggestible people can form false memories that are incredibly detailed and so realistic they are indiscernible from real memories. There have been cases of therapists who believed their patient had a repressed memory of abuse coaching their patient and in doing so created false memories. At the time this is what they looked for in Dylan’s case and found she susceptible to false memories. This does not make it her fault.
As for how she came by these memories it’s impossible to tell. The bottom line is that she believes them to be true so she needs counselling to help heal from the trauma. Just because she thinks it was real doesn’t make it so and doesn’t mean she was really abused.
However, I think Woody Allen is gross (and I’m not a fan of his films) and clearly disturbed as he married his step-daughter (or adopted step-daughter or however they were related) but that doesn’t mean he’s disturbed enough to molest his daughter. Btw I am in my last semester of a degree in psychology and have studied false memories.