The point went over your head, in any failed dynamic there are always mistakes made on both sides. I'm trying to encourage her to think deeper (not write) about it beyond not catching the "warning signs" which places her in a victim position. Whether she was or not, victim cycles create repeat patterns until the person sees their own role in it.

I'm encouraging psychological healing. I've very much been through a very similar experience.

[EDIT]

It actually sounds like it turned out well since she did end up with a solid co-founder relationship anyway. I'm leaving this up for posterity but now think my thoughts on this are unwarranted.