Rebecca Wait’s new novel invites inevitable comparisons to Meg Mason’s runaway success Sorrow and Bliss. Both are about a pair of sisters; both grapple with madness, mad women and intergenerational trauma. Both are actively funny – because of, rather than in spite of, their subject matter. And both are sharp and wry, written with a clever and unusual clarity. To fail to make the connection would be to miss the obvious – and yet both books rather suffer in the comparison. To dwell too hard on the similarities renders them a blur of high emotions and waspish comments, one a little more composed, the other a little more immediate, demanding a favourite where no favourites need be played. Much, you could say, like sisters.

At the opening of I’m Sorry You Feel That Way, Alice and Hanna are twins in their early 20s whose mother, Celia, has spent her life in the kind of seriously troubled mental state that can pass under the radar of everyone but her children. They are all attending the funeral of Celia’s older sister, whose schizophrenia dominated Celia’s early life. This funeral functions as a family reunion: Hanna has not spoken to Celia, Alice or their brother Michael in several years. Some kind of dramatic rift has occurred between them, and it is this, and the healing of it – or not – that drives the plot.

Wait’s deft handling of the intricate web of family connections, as well as her genuinely funny observations of everyday life, land somewhere between the early novels of Maggie O’Farrell and the later work of Barbara Trapido. Like them, she understands that tragedy and comedy go hand in hand.

At one point Celia dolefully explains that friends are “something other people get to have, and she does not”. Everyone in this novel knows exactly what they don’t have – where they fall down while others might fly. This kind of weighing up is familiar to sisters: the pretty one versus the clever one, the fat one versus the sporty one. This is a book about longing, as maybe all good books are.

And it is a good book, if not a perfect one. I’m Sorry You Feel That Way is, maybe, a little too clever; a little too eager to please. But then so is its heroine, Alice. In an age when bookshops are heaving with disaffected young women who drink too much, smoke too much, have unsuitable sex with unsuitable men, enjoy none of it, and who are probably (what a coincidence) writers themselves, thank god for Alice, the people-pleasing “natural victim” who is the beating heart of this one. “You never mean anything, do you, Alice? Things just happen to you,” Celia snaps at one point; and sadly Alice and reader must both agree.

As a child, Alice makes tiny doll’s houses out of shoeboxes that she won’t let her sister fill with dolls, and this is exactly her problem: she cannot bear the idea that things might not go right, and so she does nothing at all. That’s not entirely fair; Alice is trying to make things happen. But she inspires this kind of sweeping statement, even from a reader. She feels horribly real, like someone you know and want to shake; or, possibly, offer a cup of tea and the number of an excellent therapist. I loved her.

Wait handles all her characters with dexterity and charm. The book shines brightest where Wait lets herself loose on an array of supporting cast members: Hanna’s Oxford university flatmates, with their crystals and newly acquired “signature styles”; Michael’s wife, Olivia, declaring that “I’m very sensitive to paracetamol”; Michael himself, caught on TV exclaiming “It could have been me!” in the aftermath of a tragedy.

I’m Sorry You Feel That Way skirts around the edges of being a family saga, with a narrative that jumps not entirely successfully between perspectives and generations. Interludes with unstable Hanna, unsettling Celia and other characters are revealing, but it’s somehow destabilising to know more than Alice knows. It doesn’t help, perhaps, that Hanna is one of those heroines: ultra-clever, disaffected, damaged, incredibly cool even in the face of sweeping mental illness. The moments where Hanna softens are tender and lovely, but I was too much with Alice to feel anything except edge-of-my-seat fear that Hanna might change her mind again.

Hanna’s mental illness, and her aunt’s before her, are managed with skill and insight, but somehow it’s not this that sticks with you: it’s the ferret on the loose at a party, the shoebox doll’s houses, and the fleeting, gorgeous moments of real happiness.

• I’m Sorry You Feel That Way by Rebecca Wait is published by Riverrun (£16.99). To support the Guardian and Observer, order your copy at guardianbookshop.com. Delivery charges may apply.