Girl keeps postponing first "date"?

I have asked a girl that I am interested in, if she would like to go for coffee with me. She is always quite busy with stuff so I have been giving her the ability to pick when we will go. It has been almost 6 weeks now and she has postponed 5 times. From her messages it sound like she really does want to go out for coffee with me, but is too busy. When she suggests a date I have always said that I am free that day. So my question is, is she interested in me, trying to find out how much I am interested in her by making me wait? Or is she not interested in me, putting me off till I lose interest in her?

Thank you, have a great day.
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So we finally had coffee yesterday, she told me just how busy she has been. As we got up to leave, she, suggested that we have coffee again. I began saying that since she had the busier schedule, that she should let me know when she would like to go again. But she interrupted me saying that it was the season, and that she would be less busy in the future.

So I guess my optimism was not unfounded. But thanks for your input.
Girl keeps postponing first "date"?
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