I don't have a copy of Mary, and have
never read it. But the plot you outline is a very familiar one to me. I
have just read it in Oscar Wilde's The Picture of Dorian
Gray.
The Plot: A beautiful and innocent young man is inspired to
seek out life and experience under the influence of a young nobleman's
suggestions. He finds it in the theater, in the person of the actress Sybil
Vane, for whom he forms a passionate attachment. He courts her until she falls
in love with him, which for some reason takes away her acting ability. When she
disappoints in the role of Juliet, he callously throws her off and she commits
suicide. Of course one of the themes of Dorian Gray is change, moral and
physical. Death stops that process for Sybil Vane. Dorian's own moral
degeneration is registered only in his portrait. It's a famous story,
beautifully written, most unjustly unread. Must be read by every
Nabokophile. ASAP.