I know that you have already received a lot of tough love on this thread, but I think you really needed to hear it. You need to go to the library and borrow a Suze Orman book, asap. She will strongly disagree with your claim that you are financially responsible. Before making any discretionary big purchases (like, say, a wedding), Suze recommends that you have an 8-month emergency fund. That’s 8 months of rent, car payments, living expenses, etc. It is quite evident that you didn’t have that before you moved, and you said yourself that the decision to get married came after your move.
At this point, you need money, and fast. I would walk over to your closet, and pull out about half of the outfits to sell on ebay. Especially if you have nicer stuff, you will make money that way. I regularly see people spending over retail buying stuff from Anthropologie on ebay. Movies you’ve already watched, books, video games, all of that stuff goes for good money on ebay and half.com. You said that you have a storage unit, which means you have stuff that you are not using. Any of the furniture, sell on Craigslist. Chances are the money you make selling stuff is going to be more than what you would lose by cancelling the wedding now.
Cutting your discretionary spending for two months can actually make you a lot of money. Cable/internet bill: $200. If you go to the movies once a month, $35. If you go out to dinner once a week, $320. If you get coffee out twice a week, $50. Cancel Netflix, $20. Bringing a sandwich instead of eating lunch out, $200. If you drink a bottle of wine a week, or a 6-pack of beer, that’s $80. Right there I saved you over $700. It’s not going to pay everything you owe, but it puts a dent into it.
I have to agree with everyone’s comments about cutting the band. Even renting good speaker equipment will cost you much less. Return the shoes if you can. You’ve mentioned that your wedding is fairly casual, so could your FH wear something he has instead of a new suit? What about khakis and a blazer, or khakis and a nice shirt (I’d imagine he will be quite hot outside in Texas in a suit).
Finally, I have to suggest that you sell your engagement ring, or return your wedding band. I looked at your profile and saw the other thread where you posted a picture of them, and I think that your ring would bring in quite a bit of what you owe.