<human>: Could you distill the essence of the text into 1-3 sentences?

Okay, so I have been working with this girl (we'll call her Kelly) for a year. We work in a small store in retail and often work together. She is a nice girl and everything, and when we work with others at the same time we talk just like normal. But when it's just us working together we barely say a word... and the tension is just awful.

I thought it may have been because she just didn't like me, however we hired a new girl (she can be Jenny) recently (18) and yesterday she spoke to me privately and said that Kelly also doesn't speak to her when they work together. We work with three other girls who have all worked with Kelly for about 5 years and they all speak and get along fine.

I guess my question is how can I make it less awkward when I am working with Kelly? I have tried EVERYTHING I can think of to make conversation, but she will talk for a short while and then she just doesn't make the effort to continue it. We end up just standing right next to each other not saying a word for hours.
<bot>: My co-worker doesn't make any effort to make conversation with me when we work together, what can I do to make shifts with her less awkward?