I was just reading this and realized how similar it is to my own life - I once had a friend who stabbed me in the back. I honestly think you can't be friends with a business partner and I now realise that they were only my friend because I was useful to them.
https://www.dailymail.co.uk/debate/article-7474805/SARAH-VINE-gives-intensely-personal-emotional-response-David-Camerons-memoirs.html