The Portrait of a Lady
How we cite our quotes:
[Mrs. Touchett] was virtually separated from her husband, but she appeared to perceive nothing irregular in the situation. It had become clear, at an early stage of their community, that they should never desire the same thing at the same moment, and this appearance had prompted her to rescue disagreement from the vulgar realm of accident. (3.1)
To Mrs. Touchett, love is secondary to convenience; she views her marriage as a pragmatic arrangement, above all.
It may be added, in summary fashion, that the imagination of loving – as distinguished from that of being loved – had still a place in [Ralph’s] reduced sketch. He had only forbidden himself the riot of expression. (5.5)
While Ralph is convinced that his tuberculosis prevents anyone from loving him, he still retains some faith in the idea of loving someone – cue Isabel.
I came to England simply because you are here; I couldn't stay at home after you had gone: I hated the country because you were not in it. If I like this country at present it is only because it holds you. (11.14)
Love, to Caspar Goodwood, is obsessive and all-encompassing; without Isabel, he cannot be happy.