C.P.
Hugs to you, mama! Your post reads like you are tired, too. It can be really frustrating to deal with a newborn who seems like she should be fine but still wants to nurse and be held all the time. It doesn't seem like it should be, but it is frustrating and hard to spend your days nursing and holding a baby, especially when there's a preschooler needing attention, a house that needs attention, a family that needs feeding, laundry that needs doing...Sorry, I don't want to make you feel worse, I just want to say that I understand where you're coming from (I have a 3 mo old, 2 yr old, and 4 yr old).
That being said, please don't feel like you have to break your baby of any habits. Credible research really says that babies this age cannot be spoiled. Their wants are their needs and the healthiest thing for them is to meet their needs, even if it means nursing an insane number of times.
The question of course is how to maintain your sanity at the same time. I agree with other posters that getting a sling of some kind if you don't already have one can really help. At least then you will have both hands free for getting some things done while still holding your baby. Personally, I would strongly recommend a stretchy wrap (like the Moby or similar) for long-term comfort. I also have a bjorn and a pouch, but the wrap is easiest and most comfortable for me. You can pm me if you want help with this all. Also, there's a BIG difference between letting your baby cry it out and letting her cry for 10 minutes while you take a shower. Hopefully your husband is understanding and can help out. And if you have other friends or family that can help, ask them too!
Finally, this is just anecdotal, but it was one of the most helpful things that ever happened to me. When my second daughter was a newborn she also wanted to nurse and be held ALL the time. When she was four months old, she and I went to visit my newborn nephew. I couldn't believe it, but he didn't want to be held all the time. He would cry and cry if you got too close and cuddly with him. He would only fall asleep if you laid him in his crib. If you tried to rock him to sleep he would just get more and more agitated. My bro and SIL are completely opposed to letting a baby cry it out, so I knew this wasn't where it was coming from. When I talked to them about it, they said they were baffled by this at first, but said that when they finally recognized that this is who he was, and worked with it, he was much happier and more settled. So I could see that there really are some babies who like to be put down to sleep and that's okay. What's more, I could see that my daughter was nothing like that and there was nothing I could do to make her be that way, as much as I sometimes wished that I could just lay her in her crib and have her be happy to fall asleep on her own. It also made me appreciate my cuddly girl, because the other side to it was that I could cuddle and snuggle with her to my heart's content, I could comfort her anytime just by holding her close or nursing, and (as she got older) I had a baby who loved to give hugs and kisses and that's a pretty nice baby to have! My nephew, on the other hand, was hard to comfort when out and about since he needed his own quiet space. I know this has been really long, but what I'm trying to say is that that experience really helped me to accept my daughter as she was, not as I wished she would be. It took away a lot of the guilt I was having about not letting her comfort herself more. I was still tired and behind on the laundry, but I was more okay with it, and that helped me more than anything.