For it struck me after she finally went away [...] that I really would like to talk to somebody about my grandparents, their past. (1.3.67)
Lyman may act like he wants to be left alone, but even he can't handle long-term isolation. We don't think there's a person out there who can. Regardless, Lyman is craving human contact so much that he even wants to hang out with Shelly—which is saying a lot for him.
So in one stroke her picnic in the West has turned into exile. The three thousand miles [...] revealed themselves as a continent. (2.2.18)
At first, Susan doesn't feel all that isolated when she moves west. That changes when Augusta's first child passes away. Susan wants so badly to be there for her best friend in her time of need, but she knows it would be impossible for her to afford the trip.
Oliver was gone from before seven until after six, six days a week. She lived for the evening and for Sundays. (2.2.29)
It certainly doesn't help things that Oliver works constantly, leaving Susan home alone all day with nothing to do but twiddle her thumbs. Man—what she wouldn't give for a Game Boy and a Tetris cartridge right now.
"When you're here I love it. Look at it, who wouldn't? It's wonderful for Ollie. But when you're gone I go crazy with boredom and loneliness." (3.2.34)
Isolation has a way of making even the most beautiful locales feel claustrophobic. Just look at this one: even though Susan lives in a beautiful home right on the beach in sunny Santa Cruz, California, she feels more like she's a guest star on Orange Is the New Black.
I know what she thought of Father. He was such a gloomy man [...] just sat and stared at nothing for hours at a time [...] Lived in some world off by himself. (4.1.16)
While physical isolation is a big part of Angle of Repose, we see countless examples of psychological isolation as well—especially where Lyman's dad is concerned. Although we don't fully understand the traumatic events that caused this isolation until the end of the novel, we see its consequences throughout the book just the same.
"It is during this hour of freedom, such as it is, that I realize how close to imprisonment is the life of a Mexican woman." (5.4.20)
Although Susan falls in love with Mexico, she simply can't abide by the country's sexist views. Sexism in America is bad enough, but women in Mexico are expected at this time to remain completely separate from men, leaving them isolated, bored, and alone.
"But I love you, my darling, do you see? He's kept you from us for five years, he's taken you out of the world you belong in." (6.1.74)
Augusta isn't too happy that Susan lives halfway across the country, either. The two girls spent their entire childhoods planning their lives together as if they were spouses, but those hopes and dreams were shut down in an instant. It's a real bummer for both ladies.
She knew that sooner or later [...] she would be packing up her children and [...] going West again—not, as at first, on an adventurous picnic [...] but into exile. (6.2.98)
At first, Susan believed that her family would spend a few years out west before returning home to the East Coast. Things don't quite turn out as planned, though. Instead, Susan is forced to come to terms with the fact that she might never see certain members of her family again.
Like a widow, she was, grim and diligent to support her brood. She does not sound unhappy, but in two separate letters she refers to herself as one "who wants above all to be alone." (8.1.9)
After her marriage begins to crumble, Susan starts believing that she deserves to be alone. It's hard to blame her for feeling this way: she's had an extremely stressful life struggling to raise a family in the West and could honestly use a break. But, Susan is only able to stay in this self-imposed exile for so long before returning home to the people she loves.
Am I feeling my isolation threatened? Do I hear Rodman and Ellen and that cat's-paw of a doctor conspiring to move in and capture me? (8.2.4)
When push comes to shove, no one in Angle of Repose is more isolated than Lyman himself. In fact, the real reason why he's so afraid of Ellen is that she presents a threat to this self-imposed exile. If the end of the book is any indication, however, Lyman might be reconsidering this mindset.