Hi -
I agree with the attachment parenting technique. I can imagine the baby could be feeling insecure b/c she'e away from her parents. If you carry her around in one of the before mentioned carriers she will eventually feel more secure. Then, she'll probably want to play with toys and be on her own. She is probably soothed in the swing because it reminds her of home, or mom/dad. I used an awesome carrier for attachment parenting for my son. It's called The Moby Wrap. It's a REALLY long piece of fabric that can be wrapped around your body all different ways (depending on the age/size of the baby). It's really comfortable because it supports the weight on your hips instead of shoulders. Here's the website for them:
http://www.cherubtyme.com/products.htm
I hope things get better for you. I can imagine how tough it must be.