I need to cut up paragraphs into their constituent sentences. I also want to calculate with abreviations and decimals containing dots in the middle of the sentences.

My simplistic definition: A sentence starts with a capital letter, finishes with (.?!) followed by a space and the capital letter of the next sentence, plus something that is NOT (.?!)
I came up with the following negative look- ahead solution that works on decimals, but fails on abreviations.


The negative look-ahead should fail - and come back with true- till it arrives at the sentence ending position in my definition, but it doesn't..
I would appreciate an explanaton for its failure.

Just after daybreak in Nags Head on the Outer Banks, about 200 miles northeast of Jacksonville, winds 85.43 miles / hour whipped heavy rain across the resort town. Tall waves covered what had been the beach, and the surf pushed as high as the backs of some of the N.Y. dt. houses and hotels fronting the strand. Lights flickered in one hotel, but the power was still on.