Re: How did you get through the first part?
You need support momma!!! Have you talked about your worries with your DH? I would start there and explain how important this is to you. I would have stopped nursing at 6 weeks if not for hubby. He just wouldn't let me. Period. Nursing sessions were awful and usually included me crying. Luckily we had talked at length prior to baby and he was very educated about breastfeeding. After DH I would rally your all friends and family who might be helping you. Have resources ready ahead of time. A friend who can come over or that you can call. Come here and ask for support. Whatever helps you.
What also helped me and I know that not everyone would agree with this, but I needed breaks from time to time. Having a good quality breastpump so that DS could learn to bottle-feed was wonderful. Just having DH give him one bottle a day of expressed milk helped me keep my sanity. The pump has also been valuable in helping through times when my supply needed a boost.
Good luck...and remember no matter the outcome you're a wonderful momma. Be committed to BF, but don't be hard on yourself.