He already admitted this to Jason or Sasha. Maybe I can find the scene. Paraphrasing here but Mikey basically said:
Looking back on her history, there is a pattern. Willow has always had a hero complex. She likes to be rescued and develops feelings for her white night. He went as far as saying that Drew rescuing Liesl and bringing her home to be her donor is what caused her attraction to Drew. He also used himself in the equation but I don't remember the event he said. I think it was how far he was willing to go to save Wiley from Nelle.
Anywho, this is a perfect example of why I say that he walks around like his $hit doesn't stink, when in reality--Mikey, Chase, and Drew are in the same boat where Willow is concerned. They all fell for the damsel act. Chase less so (initially) because when they first started to date, Willow was a teacher and I do not recall her being in any danger where Chase had to ride to her rescue.