Is it normal, i can't stop thinking about her.

Just some backstory.
Ok. So I am 20 years old, live in CA, go to UCLA, and have liked many girls in the past, and have had many girls like me, but i've moved on pretty quickly.
This one's a little different..

Now, my mom has a friend from college, who she rarely talks to (last time was in Sept.) who has 3 daughters. Our families used to do stuff together, or so i'm told, but I don't really remember anything from the meetings. The last time our families met was like 3 and a half years ago. So here's the thing; about a year ago we received an innocent family Christmas card with a picture of the whole family, and I became hooked! This girl, epitomized everything I want in a girl. Beautiful, Christian, from a good family, even my mom when i was younger used to say "you need to marry one of those girls". The worst part is she, lives in Alabama, though her parents live in Nevada, and her sisters are in california. I have become obsessed, i've facebook "creeped" for a year now,and this has only confirmed my feelings for her. I did find out she has a bf, but it almost has no effect on me. I feel like this is the girl, that god has promised me, and I still feel there's a chance.

What should I do!!??
I don't know if i should add her on facebook (zero mutual friends, really random, i barely remember the meetings), but I feel like something must be done, as impossible as it seems, i feel there's a chance!
Please give me some words of advice, what should i say if i add her on fb? should i add the whole fam too? why should i add her?

Is this normal!!??

I'll take anything and everything!
Thank You