What is the meaning of [Worse things happen at sea]

We say this in a resigned tone when we find ourselves in an awkward or
difficult situation, or when we have to put up with something less than we
expected.

> ‘The butcher hasn’t delivered the joint ‘ said Mrs Jones, ‘so I’ll have to
open a tin of something.’

> ‘Never mind’, said her husband. ‘Worse things happen at sea.’