Complex sentence: At the "Why Did I Get Married?" ceremony, Patricia announces to the group that she and Gavin are getting a divorce, causing an upset Gavin to walk away from her, because he did not know she was going to announce it to them.
Split into simpler sentences: At the "Why Did I Get Married?" ceremony, Patricia announces to the group that she and Gavin are getting a divorce. Gavin walks away from her, upset, because he didn't know she was going to announce it to them.