Hmmm. Insecurity issues? Sounds like the OP has no issue with the trip and even if he did, he has no say over what she does. I certainly wouldn't be sitting around worried about it if I were at home while she was there.
Wet Willies on South Beach was cool for NYE one year. Spring break of 80 was not a fun one in Miami. Got stuck in the middle of a race riot. South beach, hot hot girls, topless and the like. Lots of parties and clubs. She'll dig it there.