If you have got married and realised you have made a big mistake you can get divorced. In order to get divorced you need to invite your sim’s partner over to their house and when they are in the same room initiate a conversation. All you need to do at this point is select 'More Options' on the 'Conversation' menu and choose 'Mean' followed by the 'Divorce' option. After some uncomfortable conversation the divorce will be complete. Unlike real life there is no consequences from separating aside from a broken friendship with your sim’s former partner. Your money, house and asstets remain intact.