Sorry to say but this sounds very ridiculous, it clearly shows you are not yet ready to marry. Perhaps this should be a wakeup call for your would-be bride to make better decision

You should already know btc price will start to rise rapidly at some point and should not be enough reason to halt any real life event for.
I hope you can take advantage of the upcoming bull market because some people can get carried away during this period and ended up not doing as they intended.
OP is married already. What he thought about doing was to celebrate his marriage anniversary. Which i feel selling off his bitcoin for a marriage anniversary party is totally pointless. It is a bad idea, i won't think about it twice ill refrain from making such a decision. OP can get a Boquete of gift from his emergency fund or any other surprised present for his wife, or still take her out personally to a reserved hotel and have a romantic dinner night. This is a better way to celebrate anniversary instead of spending unnecessary by throwing a party to celebrate it. Funny enough all these expenses can be done from his emergency fund.
Unless, unlike other investors that forget to keep emergency funds when investing. This is the kind of situation they later end up in the future. Not is a good time to start saving that emergency funds so that next year anniversary OP could have enough to celebrate his anniversary. Tempering his bitcoin investment i=would be a regretful decision that he will make.