The short answer to that last question is that it usually takes survivors a long time and a lot of work to stop feeling that way. And it is generally even harder for incest survivors, especially the earlier the abuse started, because the more you've generally internalized the idea it's your fault.
I don't know what will ultimately work best for you, but one thing you might try when you feel like that is to just kind of walk yourself back through the steps of what happened, understanding that how any abuse started is that
someone decided to abuse someone. How can it be up to you, or anyone else BUT that person, what happened? After all, if they had not decided to abuse someone, no matter what you did or didn't do, they wouldn't have abused you. Does that make sense?
It may be that for a good while still you have to often do little thought and reframing journeys like that in your mind when those feelings of it being your fault or somehow about what you did come up. The good news is that the more time that passes and the more what you're thinking is coming from truth-telling places like that, and not from things like abuse that victim-blames, culture that victim-blames, the less often you'll find your head in that trap and the easier it will be to get rid of those thoughts when you do still land there.