The word vintage literally means "of age." With such an open meaning, there are many interpretations. Most antique dealers consider an item to be vintage if it is at least 40 years old.
Vintage love, I define, is a state of relating in which all people are skilled practitioners of the Biological Dream skills. It involves two or more trained people and is the result of years and years of learning.
An antiquary or antiquarian is the usual term, though they tend to be used for those who do more than just love old things, perhaps they collect them or research them. Some rare and obsolete terms (which may be especially apposite) are palæophilist/palæophile and philarchæist (someone who prefers old things to new).
A vintage theme is one that uses items and decor that depicts a certain period in time, or the items themselves are aged. For instance, an old suitcase used for cards, a 1950's pickup truck as a getaway car, an antique typewriter as a guest book, lace and floral china, are all examples of decor for a vintage wedding.
vintage modern—design style makes full use of items with history that are either not part of a particular design style, or are. A vintage modern design style focuses on mixing the old with the new; maybe even something borrowed and something blue.
A generally accepted industry standard is that items made between 20 years ago and 100 years ago are considered "vintage" if they clearly reflect the styles and trends of the era they represent. Items 100 years old or more are considered antique.