iliskimizi bitsin arkadas olarak kala biliriz.....

many thanks

our relationship is over.. we could be [stay] friend...

thanks for the quick reply, how do I say is he having a laugh, in a polite sort of way

Having a lough is likely to cause misunderstanding in the translation. It has too many meanings. Maybe you could explain with other words.

Is it something like this you want to say:

Şaka mı yapıyorsun? : Are you kidding?

more polite:
Umarım şaka yapıyorsundur. I hope you are kidding.

I sent the last, much appreciated, my turkish is just not up to this

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