You touched on something that's been bothering me for a while, ever since I realized that my mom had an emotionally inappropriate relationship with me as a child.
I'm starting to think it was her poor boundaries she exhibited with me that set me up for molestation by my older cousin. My mom didn't model healthy boundaries for me, all while emotionally / psychologically neglecting me. I needed affection and love and attention, which she hardly gave.
Had she had good boundaries with me, I doubt I would have had an sexual relationship with my cousin as a child.