Tom Cahalan

Quick Facts

• Role: Father of Susannah Cahalan; ex-husband to Rhona; husband to Giselle
• First appearance: Early in the memoir, as a reserved, practical parent whose distance contrasts with Susannah’s escalating symptoms
• Key relationships: Daughter Susannah; ex-wife Rhona; Susannah’s boyfriend Stephen; second wife Giselle
• Presence: “Average height and build,” but nicknamed “big man” by a babysitter—shorthand for his commanding, intimidating aura that becomes a protective asset in the hospital

Who They Are

At first glance, Tom Cahalan is a classic stoic father: emotionally guarded, allergic to sentimentality, and more comfortable with action than talk. As Susannah’s behavior unravels and her illness intensifies, his restraint converts into focus. He becomes the blunt instrument of love—showing up daily, keeping vigil outside a closed door, pushing back on doctors, and recording every step in a private journal. The “big man” presence that once read as intimidation turns into sanctuary. He embodies love as logistics, protection, and endurance: the kind of caregiving that doesn’t say “I love you” but proves it, minute by minute.

Personality & Traits

Tom’s defining qualities—stoicism, protectiveness, and resolve—surface as the crisis escalates. His reserve isn’t indifference; it’s armor he’s long worn, and the memoir shows him taking it off piece by painful piece.

• Stoic, emotionally reserved: He “habitually avoid[s] words like ‘I love you,’ even with his children,” and tells Susannah he only kissed his own father on his deathbed—evidence of a learned, generational guardedness.
• Fiercely protective: He threatens a reluctant cab driver during one of Susannah’s episodes—“You better fucking drive. Don’t you dare stop.”—and later ejects an insensitive medical team from her room when they discuss ovary removal within earshot.
• Steadfast and determined: He vows to be at the hospital every day and follows through, even when Susannah’s Capgras delusion bars him from her room; he creates a shared journal with Rhona to track care, treatments, and questions.
• Deep care beneath the surface: He cooks her favorite meals and invents a grounding motto—“What is the slope of the line?”—to frame recovery as incremental progress; Susannah sees him cry for the first time, revealing the cost of his vigilance.
• Commanding presence: The babysitter’s “big man” nickname becomes literal in the ward, where his size, voice, and certainty deter negligence and keep focus on his daughter’s dignity.

Character Journey

Tom’s arc moves from distance to daily devotion. A “once-every-six-months” dad by Susannah’s account, he’s jolted into action during the terrifying night at his brownstone, when her psychosis accuses him of kidnapping and violence. From there, he refuses to look away: sitting in hallways when she won’t see him, challenging clinicians who treat her like a case instead of a person, and coordinating with Rhona to present a united front. He sheds inherited stoicism to meet the crisis on its own terms—trusting a brain biopsy despite deeply ingrained fears and revising his snap judgments, especially about Stephen. By memoir’s end, Tom has remade himself not with speeches but with stamina, transforming a fractured relationship into a hard-won bond forged in the daily grind of care.

Key Relationships

• Susannah Cahalan: Susannah’s delusions turn Tom into both target and anchor: she accuses him of violence one night, then refuses to see him in the hospital. He stays anyway—reading in the hallway, bringing food, and reframing recovery with the “slope of the line” mantra—so that when her mind clears, what remains is his unmistakable presence.

• Rhona Nack: Though they struggle to be in the same room, Tom and Rhona build a high-functioning co-parenting system, communicating through a shared journal and dividing tasks. Their uneasy alliance becomes a living example of Love and Family Support: love made practical, not pretty.

• Stephen: Tom initially pegs Stephen as a “placeholder” boyfriend. Watching Stephen’s consistent, calming presence at the hospital, Tom revises that view, recording his respect in the journal—a quiet admission that devotion, like Tom’s own, is measured by who shows up and stays.

• Giselle: Tom’s second wife often works offstage—cleaning Susannah’s apartment and absorbing Susannah’s paranoid accusations that Tom is beating her. Her composure expands Tom’s support system and underscores how caregiving radiates beyond the patient.

Defining Moments

Tom’s most consequential choices come when he refuses passivity—insisting on safety, dignity, and forward motion even when the path is unclear.

• The Night at the Brownstone: Susannah’s psychosis erupts—she accuses Tom of kidnapping, tries to flee, and hallucinates him beating Giselle. Why it matters: It shatters denial and pushes Tom from worried parent to emergency-mode protector who understands the need for immediate medical intervention.
• The Hospital Vigil: After admission, Susannah’s Capgras delusion convinces her Tom is an imposter; she bars him from her room. Why it matters: Tom’s hallway vigil redefines fatherhood as presence without permission—care that honors boundaries while refusing abandonment.
• The Confrontation with the Resident: A resident discusses removing Susannah’s ovaries within earshot; Tom orders the team out: “You get the fuck out of here right now! Never come back.” Why it matters: He reclaims agency, forcing the staff to treat Susannah as a person first, a case second.
• The Brain Biopsy: Haunted by the maxim “never let anyone mess with the brain,” Tom nonetheless consents when Dr. Souhel Najjar recommends a biopsy. Why it matters: Trusting expertise over fear marks a crucial pivot from reactive protection to strategic advocacy.

Essential Quotes

Susannah. You’ve got to get yourself together. You can’t live like this. You’re an adult. This tough-love admonition captures Tom’s early framework: problems are solved by willpower and responsibility. The line becomes poignant as the illness defies such logic, forcing him to trade admonition for advocacy and to recalibrate what “getting it together” means.

You better fucking drive. Don’t you dare stop. Delivered to a hesitant cab driver during a crisis, the command distills Tom’s protective urgency. He’s willing to breach decorum to secure safety, signaling a shift from distant father to on-the-ground guardian.

Why are you doing this? Why are you doing this to me? Raw with confusion and pain, this plea exposes the helplessness caregivers feel when love can’t immediately fix what’s wrong. It punctures Tom’s stoic exterior, revealing the grief beneath his control.

You get the fuck out of here right now! Never come back. Get the fuck out of the room. Tom’s eruption at the residents reframes the power dynamics of the hospital room. By setting a hard boundary, he demands humane care and asserts his daughter’s dignity as nonnegotiable.

What is the slope of the line? ... It’s positive. And what does positive mean? ... It means we make progress every day. Tom turns a math metaphor into a therapy: measurable, incremental hope. The mantra gives Susannah a cognitive handle in chaos and crystallizes Tom’s ethos—progress, however small, is victory.