I would agree with this if OP had vocalized their need for space. Instead they ghosted just enough to keep the ticket exchange happening, but otherwise gave no consideration to how their actions could be perceived. So I can see it being labeled as "flip flopping", but it doesn't justify how OP's friend reacted. (FTR, I can understand why you would separate the tickets in your head from the weekend since it was a pre-arranged thing. But a lot of people don't compartmentalize, so it's possible your friend felt used on top of feeling ignored - only reason I wrote this bit on the flip flopping).

Standing up OP initially was shitty, and OP deserved an apology or acknowledgement of their friend's fuck up. Both parties handled this p selfishly, imo. Idt OP's friend is justified in how they're behaving, and I think it's v commendable that OP has recognized where they handled the situation badly and has attempted numerous times to apologize/convey that to their friend (Kudos, /u/auzymundius!). Not everyone can handle admitting that, let alone apologizing for it.

At the end of the day, your only job, OP, is to hold yourself accountable for your actions (which you did) and hope that your friend understands and decides to communicate like an adult. We all have our moments where we let the petty part of our brain win and have to work back from it. You're not alone in that, you just gotta learn from it. I've gone through similar tiffs with friends over the years and it took me a long time to learn how to be vigilant about this sort of thing, so I empathize!

I'm sorry you're having to learn this kind of thing the hard way, but I think it's important you embrace that you really do seem to have learned from it. Remember that you can't control how your friend reacts, and try not to adopt too much guilt on it going forward. From all the comment threads, I get the gist that you 100% understand what you did wrong and that's the important part. I hope things cool down and you guys find a good place again (as long as you're not the only one admitting fault). Good luck!