Any way to help hairloss?

Mkay, so im 17.

Il begin with my family hair history.
Apparently both my genetic father and my uncle have bald spots on there heads. and both my uncles on my moms side of the family are completely bald.

I have been loseing hair rapidly recently, as in i brush my hair after a shower and im pulling out huge amounts of hair.
My hair is about...well if you wanna see heres a pic of me.

http://winter2dawn.deviantart.com/art/Me-and-my-cat-stewie-2-74101380

The picture is roughly around.... a half a year old? and my hair has a few more inches on it.

I have been loseing alot of hair recently, and i also have been having alot of stress due to girlfriend issues (haha figures right?)
Also i have a horrable diet (bearly eating. me being a anti-stressful-eater)

Maybe these things have anything to do with it?
But is there any proven way to keep hair? and prevent hairloss?
Cuz seriously >> i think i value my hair more then my virginity x]

Anyone mind helping?

p.s oh and btw, off topic and it doesnt need to be answerd but;
I saw this beautiful women at a vet not to long ago and her hair was bleached almost pure white with a hint of yellow, it looked awesome!
Do you think it would be a good idea to do the same to mine? and if so, how?