Didn't you ever think of getting married again?
Didn't you ever think about getting married again?
Have you never thought about getting married again?
Have you never thought of remarrying?
Have you never thought about remarrying?
They are taken to mean the same.
you can say ever or never when using HAVE
for the first two sentence a positive sentence can also be used
"Did you ever/never think of remarrying"
But "DIDN'T you never think about/of (--- --)" is a little strange to my ear
" didn't + you never" may be less common and sound not right compared to
"didn't + you ever"
see what other natives say !