Why am I attracted to men who are older than me?

I mean, I’ve never been attracted to guys my own age. When I was 11 I had a crush on my Dad’s 20-year-old employee. Now that I’m 21, I’m attracted to 30-year-old, but it’s difficult to meet men that age since I’m in university and most of them are out in the workforce. I mean, I’m really close to my Dad and I’ve never in my life been mistreated by a man. Most of them, in fact, bend over backwards to do me favours. I find guys my own age to be really drunken and overly promiscuous, not caring about the bigger questions of life or the value of a quiet life. What can I do?