I have "all sorts" in my tree. Lots of illegitimate births - it was almost compulsory
I've a bigamy where the man knew his wife was still alive - she turned up in court to prove it.
Another bigamy where they separated (through the courts on grounds of cruelty) and the wife reinvented herself as a WW1 widow to marry "a proper catch, an RAF top officer and Wing Commander" - but he got suspicious and found her husband was still alive, so he got the divorce courts to nullify their wedding.
I've one I suspect, where an illegitimate lad married in his own village under his birth name - then he and his wife appear in different counties, she remarried under her birth name and he married his half-brother's wife's sister using his "adopted name" of his half-brother (two brothers married two sisters, although years apart/not a double wedding). Nobody suspected a thing, I'm probably the first to discover this... and it's something I'd need to spend more time on "proving".
My gt-grandmother just started using her bf's surname - even though they'd both been widowed long before they met. They were certainly at the same address as head/lodger for 20 years in the censuses before being referred to in the newspapers (eviction case) where her widowed name was given and "also known as Mrs ...." the lodger's surname.
I've always been surprised that there is no "look up" list of divorces easily available to the public. You'd just need the names/dates at its most basic.... to give you a clue.