im looking for a series where a childhood friend of the girl comes back after many years and hes really different and then they fall in love.

any ideas?

Wow, that sounds pretty generic shoujo.

Maybe Bokura wa Itsumo?

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If you've ever thought or said "Nice Guys finish last" and really meant it, then you should probably read this LJ post by DivaLion. It's incredibly insightful whether you're male or female.

From a bumper sticker I like:
"If you're gonna ride my ass, at least pull my hair."

Moved to looking for forum. :]

But yeah, I say Bokura wa Itsumo also.

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Tona-Gura! perhaps?

Love Hina is comedy/harem manga about the male lead trying to find his long lost childhood friend and keep a promise made to her. But that isn't really the whole focus of the story so it may not be exactly what you're looking for.

Would Non-chan to Watashi count?
(The girl or boy didn't leave, but they didn't talk to each other for a while).

Tona-gura

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