I love this girl but she only wants to have sex?

Me and this girl have been 'sex buddies' for a couple of weeks now, and we've made a deal not to turn it into anything bigger than that. However, after just a couple of times I saw her, I began to fall for her. Weeks have past, and I feel stronger and stronger about her. I always try to talk to her, but we don't have much to talk about because she's a working woman and I'm still in school(the age difference is not big and it's legal). She, on the other hand, doesn't seem at all keen on talking with me. When we stop having sex, she just wants to leave, and I kinda miss her. I think that she doesn't even pay much attention to me, and if I didn't ask her questions, she wouldn't talk to me like at all. But, there's still something really sweet and special about her, which is why I can't get her out of my head. I saw the way she is with her friends, and she's like a different person with them - not hurrying all the time, but smiling and talking to them. She sounds amazing when she talks. But, when we started this she said that she just wants to have fun with me. Should I tell her how I feel? I can't get her out of my head, so please don't tell me to 'forget her'. She's special. But, if I tell her this, I think she'll want to stop seeing me! What to do??