I don't believe that the PSU isn't important. Just about every part of a computer is important, I just don't believe it's the most important part. A PSU can easily be replaced if it fails without having to rebuild your computer. Almost every part can easily be replaced if they fail EXCEPT the motherboard. If your motherboard fails, you literally have to tare your computer apart to put a new one in, risking frying other parts without care if you can even use some of them with a new motherboard. The motherboard dictates what parts you can use and the speed of those parts, heck, it even tells you what kind of case to use (good luck fitting that huge motherboard into that tiny case). The PSU, on the other hand, only gives power to your computer. Yes, important, but what good is a high end PSU inside a computer with a motherboard that only has PCI slots and is stuck with out dated RAM and a CPU socket?
As for you being a girl, I honestly don't care if you are. I've known girls who are in to computers just as much as we are, I've talked to them about hardware configurations and games and what not long before I even joined this site, not to mention I have a local friend who I talk to all the time, sharing information and speculating on super computers that we would want to build if we had the money.
I've had an interest in computers and what they could do since my family first got a Windows computer back in 1997. I didn't have knowledge of the hardware until I was older of course, and in my sophomore year of high school, I took an A+ class which included assembling computers (that was a fun year). Early on, I believed that if you're going to build a computer, it should be as powerful as you can make it right from the start, but as time went on, I've learned that the important thing is a computers upgrade ability, which ties into the motherboard. I don't intend to get a different motherboard until I start a new build from scratch, which may not happen for a while, as this computer is young and still has a lot of life left. Yes, as I've said before, the PSU will be one of the first internal things I will replace (I REALLY need new speakers ASAP), and the hardest part in replacing it shall be figuring out where everything is plugged in, but until then, it's serving me fine with no problems.
By the way, it's not like I just go out and buy parts on impulse.