Fill in the blanks in the following sentences.
That gift is from ___.
The secret remains between you and ___.
For the first sentence, you probably had no trouble picking me as the proper pronoun. But perhaps, for the second sentence, a little voice told you to go with I. If so, your little voice is wrong. Me is the correct answer in both cases.
Why me? Because objects, not subjects, follow prepositions. What does that grammar-speak mean? Think back to when you learned about the parts of a sentence. (Don't worry; I won't ask you to diagram one.) A subject performs an action on an object. The personal pronouns used as subjects include I, you, she, he, we, they, and it. Pronouns used as objects include me, you, her, him, us, them, and it.
Prepositions indicate the relationship between words. The most common examples are at, above, against, along, among, around, before, behind, beneath, by, down, except, for, from, in, into, like, of, off, on, out, over, since, and with. In addition to being on the receiving end of a subject's actions, objects are also on the receiving end of a preposition. Thus, it's correct to use me after a preposition, whether me is used alone or in conjunction with a noun or pronoun.
If that still seems confusing, and you find yourself unsure whether "everyone's late except you and I/me," try this simply trick: Switch the position of the words, and refer to yourself first. You'd never say "except I and you," would you? Probably not. That is the little voice to listen to the next time you're unsure whether to use I or me. Or simply keep in mind that it's grammatically correct to sing "For Me and My Gal" (although an etiquette expert would recommend "for my gal and me.")