It's a difficult question. I worked with my last partner for 7 years at the same large organisation. I was the IT Manager and she was head of Human Resources. We were both very careful not to let our personal relationship interfere with putting our business relationship first however there was an occasion where I heard her being spoken to in an abusive manner by a colleague and I stepped in and probably over reacted due to our relationship. I discovered that it's difficult not to get emotionally involved in a situation like that.