Laws of Attraction (World Premiere) starring Pierce Brosnan and Julianne Moore.

The film chronicles high-powered New York divorce attorneys Daniel Rafferty (Pierce Brosnan) and Audrey Woods (Julianne Moore) has seen love gone wrong in all its worst case scenarios - so how bad could their own chances be?
At the top of their respective games, Audrey and Daniel are a classic study in opposites. She practices law strictly by the books; he always manages to win by the seat of his pants. But soon they're pitted against each other on opposite sides of a nasty public divorce between famous clients (Parker Posey and Michael Sheen), with the case centering on an Irish castle that each future divorcee has their sights set on. Audrey and Daniel travel to Ireland to chase down depositions, yet the two lawyers who have slowly been developing a mutual attraction that neither wants to acknowledge, find themselves thrown together at a romantic Irish country festival. After a night of wild celebrating, they wake up the next morning as man and wife. Now they have to return to New York to carry on with both their surprising new situation and the ongoing court case.
Maybe getting married first is the best way to fall in love?