oh man, that is hard!
listen, it doesn't matter how long you breast feed, it's always hard to give it up. you managed to do it for five months, be proud of that. and you can still bond with your baby during bottle feedings.... it's actually easier with a bottle, because you can actually see baby's face!
is it possible to wean down to just a morning or just a nighttime feeding? i had such a hard time giving up nursing my baby that at 6 months, i weaned her down to just one morning feeding, and that worked well for us for a couple of months (until her top teeth started coming in and she started biting.... now at 9 months, she is all formula fed!). it was my way of hanging on to nursing for just that much longer.... but it was all for me.... she would've been fine without it.
take care of yourself and make sure your needs are being met. as jsfai said, take care of your physical and mental health so that you can be a fantastic mom for your baby!!!
anyway, i've been there. it tears you up inside, it really does. but after a couple of bottle feedings, you'll feel better about it (i cried with each of my three kids with their first couple of bottle feedings.... i know, i'm kind of a nut!), and once you start getting those wacky post preggo / and nursing hormones under control, you'll really start feeling better! good luck!