As I've experienced the preposition "ab" has local, temporal usages. But I was wondering if it has usage with a personal pronoun such as "dir" or "mir".
After you nothing has changed in my life. (Ab dir nichts ist in meinem Leben geändert.)
Here is a time period implied, that's why it seems to me possible after all. I don't know but that would be completely wrong. Actually this usage is very common in my mother language, especially in poetry.Maybe with more explaination I would be imply "after you left me or after our farewell".