Victims of sexual abuse often blame themselves. 

Most sexual abuse of children is perpetuated by an individual who is both older than and known to the child; a family member, a close friend, a teacher, a neighbour, a coach, a babysitter. There's a power relationship.

And more: this adult is usually in a position of trust and/or authority over the child. Violated and often voiceless, unable to communicate or frame what's happened to them, survivors carry feelings of shame, mistrust, powerlessness and guilt into adulthood.

It's far from uncommon for victims to feel that they could somehow have prevented the abuse from happening. 

The truth is, victims of sexual abuse did not and do not deserve the abuse they received nor could they have prevented it.