<human>: This will be pretty short and I probably already know the answer (that there's nothing to be done), but thought I would get some perspective. This is the first office job I've had (was my first out of college) so I am unfortunately naive and inexperienced with certain things.

My boss asked me to go to a business conference out of state. This was going to be my first trip and it was to a really cool place, so I was really excited! I wanted to get everything booked including registration for the event, but my boss was checking to see if we had some sort of special membership that would get us a discount before I did that. I got the all clear on everything else though, so I booked my flight/hotel (obviously going to be reimbursed by our company).

Well, a few days later, my boss discovered that the conference wasn't exactly what we thought it was going to be. It was intended for developers/admins of this software we use, and not end-users (me). We both agreed it made no sense for me to go, but I can go to one in October instead.

The hotel reservation was able to be canceled, but not the flight. The flight was $180, which is a lot to swallow for something I won't be getting any benefit out of. I regret that I was so eager and foolish to book these things before I had my event ticket in hand, and haven't told my boss about the flight. I don't see my company reimbursing me for this since it is no longer a business expense.. do I have to just eat the cost in silence?

Can you provide a brief rundown of the text in within 3 sentences?
<bot>: Booked a flight for a business trip that it turns out I won't be going on. Flight isn't refundable. Should I pursue getting this reimbursed anyway, or just accept that it's a sunk cost?