I have a 4 month old and still have her sleeping in a pack-n-play/bassinette in our room. I think that it is perfectly natural to check on your sleeping baby (even my husband recently admitted to doing this - and she's baby #4).
To make it easier for me, I pull the pack-n-play right next to our bed. This way I can just lean over to peek or listen for breathing. It makes sleeping much easier. Obviously, you can't watch her 24/7 and you won't be healthy if you try. I read some of the other posts and some Moms seemed to benefit from having the baby in another room. Find out which one works for you. With baby #4 I actually slept with her on my chest in a recliner or propped up with pillows in our bed for the first 2 weeks.
One of the other Moms mentioned the baby getting lazy. I had forgotten, but this always seems to happen within the first 3-5 days after birth and seems to be especially prevalent for jaundice babies. This is one of the more frustrating times for breastfeeding. It is difficult to purposely try to wake a sleepy baby to latch on and I had to relearn how to wake them (changing diapers, tickling their feet, and undressing them). But, it is very important to continue feeding to increase bowel movements and rid their body of the bilirubin.
Breastfeeding is different with each child and I quickly found out that it is not easier after the first child. One word of advice. Persistance.
For me, the main trick, is to either wait for her to open her mouth as wide as possible which usually means waiting until she is VERY unhappy (read that as screaming) and then squeezing as much of the aerola in her mouth as possible. If she doesn't latch-on properly, I break the latch by sliding a finger in the corner of her mouth (breaking the seal) and make her latch on again until we get it right. I have had times, where I was so engorged, that I had to pump a tiny bit for her to be able to latch on properly.
Also, with my other daughter, we introduced bottles (hoping to alleviate some stress/pain from poor latch ons) which created "nipple confusion." Basically, she became lazy because traditional bottles/nipples don't make them work as hard (the milk comes immediately) whereas with breastfeeding it does take a few minutes for the milk to be released. In my childs case, she would latch on, become frustrated and then pull herself off. It was very frustrating for both of us. Once I stopped using the bottles, and just fed on demand, things were much smoother.
Also, in my humble opinion: if you have to use bottles (night feeding by Dad, or pumped milk) make sure to get the newborn or #1 nipples. These release less milk so that the baby has to work for it. If you use a #2 or #3 stage nipple, the milk comes rushing out and increases their frustration with nursing. You can test the bottle nipples when washing them (fill with water and squeeze). If it comes gushing out, switch nipples.
Also, I made sure to show my husband (when bottle feeding) to put as much of the bottle nipple into the baby's mouth. This also helped to avoid poor or smaller latch-ons.
Hope that some of this advice helps and don't give up. I used to say that it took 2 weeks to get comfortable with breastfeeding. After my last daughter arrived, I've changed my opinion to 4 weeks+. Hang in there!
P.S. One of my very favorite nursing products is a nursing pillow called "My Brest Friend." We have a boppy, but it just doesn't support the baby as well. This pillow is very firm, has back support for Mom and a curved pillow for head and babies bottom. It was a lifesaver with my last 2 children. I think that we purchased ours at a Babies R Us for about the same price as the Boppy.