Travelling Around Diyarbakir, Mardin, and Sanliurfa

Welcome to the forum Meghan!If you scroll through the forum page a bit there is a recent trip review from a forum member Kras232b and another member also recently there has commented on the same thread.So that gives you a start for info.
As things are right now avoid Diyarbakır unless you have to make bus connections there,but Urfa(also for visiting Harran from there too) is fine as is Mardin city centre.In Mardin Province outside the city there are some area's which are now militarised zones and off limits.
I also know of someone else(not a forum member)who was in the Urfa area over Kurban Bayram week before last and they had a great time there and were made very welcome wherever they went and at no time did they feel unsafe.You'll see a lot of refugees hanging around the streets there but they are to be pitied rather than feared.

Thank you Sarikanarya for your help!

I'll second Sarikanarya on that. Just to add that at Diyarbakir the bus station/s (separate ones for long distance and more local minibuses) and also the train station are outside of the city walls. It doesn't cost much to take a taxi from one to the other.
We did that trip last year, taking the train from Ankara to Diyarbakir. We gave that city a miss, but everywhere else we went we were received with open arms. This year, however, I'd avoid Gazinatep as it's the 'dormitory town' for people going to join Daesh (ISIS). (Last year was ok, though the otogar felt a bit 'wild west'.)

This year, however, I'd avoid Gazinatep as it's the 'dormitory town' for people going to join Daesh (ISIS)>

In other words just as harmless as Paris, Bradford or Antwerp...

I'm personally avoiding Paris, too!

Can anyone tell me if Trabzon is ok to go to this time of the year? I was hoping to go there in November

Yes,it's fine but do be aware that Sumela Monastery is currently closed for renovations until spring at least.That is the main reason for people to visit Trabzon and I'd hate you to make a wasted journey.

@mothercourage So coming from Mardin, transferring at Diyabakir in order to catch a bus to Istanbul, I wouldn't even have to enter the city? Not sure if I got you right...
Do you know more about cost of transportation around Turkish Kurdistan? Like how much trips from Mardin to Diyabakir are?

Mardin,Midyat and Kızıltepe to Diyarbakır are by local minibus service so that will be cheap,maybe c.5 or 6 TL.
BTW,from Mardin why not just take a bus direct to Istanbul?Why change in Diyarbakır?You could even fly although flights on that route do tend to be a bit pricey.