why doesn't st.Clare Mary the girl from the north

Augustine St. Clare goes to college in the North and falls in love with a woman who he plans to marry. When he goes home, he receives a letter from his lover’s guardian. THe person states that by the time the letter reaches him, his lover has been married to somebody else. Augustine goes crazy and marries somebody else who he doesn't really like. He later finds out the letter was a rouse.