When Adaline and Ellis first meet

She kind of is. That's the point. The character grows out of it.

She probably doesn't want to get too close for fear that she likes him even more. Another possibility is she thinks he's lying that he's single and that's he's jut a playboy looking to cheat on hi presumed gf.

She does fancy him and yes for that moment she does have a connection, it's perfectly normal to have that physical attraction, but doesn't always mean it can go any further than that.
For Adeline, it's everything that tells her nothing can come of this, the fact she won't age, the fact she can never be honest and not only this possible relationship but any holds no future. To expect that she no longer has feelings of the dreams to have a true love and bond is unimaginable, she's still a women, she still has needs and desires, it's just that her life is so complicated, her defence mechanism kicks in, even if she is enjoying being wanted by Ellis.

Plus.....she was moving soon.

well, I look at other attractive men the same way, that doesnt mean I am looking for a relationship...It's just physical attraction