The Last Woman Of England. The Remaining series, #2

A woman in her thirties wakes to find every other person in Europe has vanished. Exploring an empty London, she claims Buckingham Palace, the Crown Jewels, and the British Museum as her own. As she learns to survive with solar power and scavenged supplies, she picks up a faint radio signal - and realises she may not be the only survivor on Earth. But first, she must crown herself queen of a silent continent.