We Are All Made of Glue: Marina Lewycka

Georgie Sinclair's life is coming unstuck. Her husband's left her. Her son's obsessed with the End of the World. And now her elderly neighbour Mrs Shapiro has decided they are related.
Or so the hospital informs her when Mrs Shapiro has an accident and names Georgie next of kin. This, however, is not a case of a quick ward visit: Mrs Shapiro has a large rickety house full of stinky cats that needs looking after that a pair of estate agents seem intent on swindling from her. Plus there are the 'Uselesses' trying to repair it (uselessly). Then there's the social worker who wants to put her in a nursing home. Not to mention some letters that point to a mysterious, painful past.
As Georgie tries her best to put Mrs Shapiro's life back together somehow she must stop her own from falling apart...