More unfortunate choice of wedding vows? (6)
I believe the answer is:
poorer
'more unfortunate' is the definition.
('poor' can be similar in meaning to 'unfortunate')
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for poorer that I've seen before include "More impecunious" , "Less well-off" , "'Having less money, fewer possessions (6)'" , "Less rich" .)