I think we are attracted to people we believe will fulfill our needs....psychological, spiritual, educational, security; various needs. And as we gain more life experience and our needs change, the people we're attracted to reflect those changes.
When we're very young, like 15 to 18, we're attracted to people who bear some resemblance to our mom or dad, either in mannerisms or physical appearance. I think that's because moms and/or dads are still fulfilling our needs at that point (generally speaking). You're even likely to be attracted to people who are similar to your abusive parents.