Conversation so far:
who does mark darcy marry in bridget jones
Mark Darcy marries Bridget Jones at the end of Bridget Jones's Baby.
why did bridget jones and mark darcy's relationship not work out
In Bridget Jones’s Baby, we learn that Mark Darcy and Bridget Jones's relationship didn’t work out because he was always working, couldn't commit, and was never there.

Question: what caused mark to break off their first first first first first first engagement
Self-contained rewrite: what caused mark darcy to break off his first engagemnet with bridget jones