It is said that girls go after guys that are like their father because their father is the only male rolemodel in their lives and thus they look up to them. You might not consciously go after someone like your father (because that would be a bit weird), but you might find that things your boy does (their mannerisms, beliefs etc) are like your father.
I used to think this was absolute crap, but then I realised that my ex- had a temper like my father and tried to control some of the things I did, like a father does with his only daughter. Even now, with my current boy, his generosity reminds me of my father, and I think that as a father he too will be as doting and devoted as my dad, but thats where the similarities stop. This is apparently why women who were raised in domestically disturbed homes go for the 'bad boys' who treat them the same way their father treated their mother, thus pretty much repeating the cycle.