Why would a man who is NOT interested in a woman continue to contact her?

In terms of texting, writing letters, etc. I mean, writing nearly everyday. No flirting, although there was some before meeting. Could it be he just wants to stay friends?

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14 d
I want to clarify my question because I'm getting a lot of answers, some are good, and make sense, and some don't make sense or are strange.
Someone here was on the ball when he asked, "Do you know he isn't interested, or are you assuming he is not? " I do NOT know if he is not interested. I said this to get some answers if he were NOT interested. He is hard to read. Yet he continues to write to me, and kept abreast of what I was doing until the very last day I was in Japan. I hope you all
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14 d
understand what I mean now.
Why would a man who is NOT interested in a woman continue to contact her?
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