I think the line phrase, "And green initials on the towels" is supposed to mean she is married. Towels with the couple's initials, likely a wedding present. I take the phrase "I should be happy now", to mean she thought getting married would fix her desire to be with this other guy who, as at least seemingly, moved on. She is in the great big house with a new husband, but still sees him as her home.
I think the line phrase, "And green initials on the towels" is supposed to mean she is married. Towels with the couple's initials, likely a wedding present. I take the phrase "I should be happy now", to mean she thought getting married would fix her desire to be with this other guy who, as at least seemingly, moved on. She is in the great big house with a new husband, but still sees him as her home.