Cannot help you with the companions, but I can tell you that the easiest trip I've ever had for meeting people was my trip through the Middle East.
Compared to a place like South America--where many people cross the continent with their significant other, and most can speak some level of Spanish so there's less of that exhaustion of communicating with locals that makes other travelers so appealing. (I don't mean that in a bad way, I prefer talking to locals and just having other travelers as the occasional break).
Language is not a huge difficulty in many of the places you are going, but I found I had to "gesture-speak" frequently in Aleppo and Gaziantep. And even in places where you find lots of English speakers, the level doesn't often allow for unbroken, in-depth conversations, so yes...that relief of meeting travelers does happen.
And for some reason, almost everyone in the Middle East seems to be traveling alone! Generally people were quite open and friendly.
The only place I didn't meet a single person was Gaziantep, which doesn't seem to have any sort of backpacker hangout (but maybe I just wasn't familiar). I stayed in a nice hotel for 15YTL and never saw any other guests. But I liked it there, the town is pleasant and the food is DELICIOUS there. Especially if you like sweets! I don't have the usual experience in Istanbul because I stayed with a Hospitality Club host instead of a hostel, but of course I met him, his girlfriend and a bunch of their friends, plus had met a bunch of people in Goreme who were living in Istanbul and hung out with them. If you do go through Goreme...very easy to meet people there, the town is so tiny.