breast feeding help.....

so, my baby is a week old today. while in the hospital, she would latch, but wasn't getting enough to fill her up, so I supplemented with formula. on day 4, we came home, and I tried to breastfeed again because I noticed my milk leaking. she would latch, but not for long, and not very well. she would latch, and then unlatch, and root for my nipple again... she starts to get frustrated & cry, so I supplement with the bottle, again. she takes a bottle fine, but I really want to breast feed her..... how in the world do I get her to latch and take my breast instead of a bottle?