Definitely
not a
disastrous experience.
1. 1.5 hours for check-in is kind of tight, especially for a less-than-efficient airport, such as IST.
2. Why escalate everything to a supervisor?! (just because you didn't like the legitimate answer)
3. Non-refundable means just that. The fact that you purchased it on Expedia is irrelevant. You failed to show up on time and your ticket got cancelled.
It must be annoying as heck and I am sorry for this. The best outcome would be to take it as a
lesson learned and move on. I've had a similar experience in CDG, but luckily my ticket was changeable for a penalty so I was able to get on a flight the next day. I didn't care about the $50 I was out; it was the experience itself that made me feel miserable. Needless to say, I don't cut it close anymore.