夫人is a formal word, usally used to introduce your wife to others in some official occations and some old ppl will used that too,cos it's an old way to address "wife" from ancient times
太太 is orgined from HK, in cantonese,they call wife as 太太 or 老婆,since when i became a popular way and now it used everywhere in China
爱人 is quite a romatic way to call your wife, it indicates that you and your wife is getting along well, and ppl will knw that u love your wife
but u can use any one of these three words, it doesnt matter, they all mean wife