making a long story short...Me and my ex have been friends for years we share all the same friends and have been through a lot of things together. Out of nowhere we started a romantic relationship everything was perfect we were best friends and so in love, i couldnt imagine a more perfect relationship. I was aware he was bipolar from knowing him all these years he was diagnosed but said he is not and is unmedicated now. He was telling me how much he loves me making future plans with me and then out of the blue i get a text saying he lost feelings im just a friend, and never heard from him again.along with me, everyone we know was blindsidded. Since we do have all of the same friends and we have functions to attend to together it is inevitable we will need to be civil or need to have a talk. i just need help understanding how they can like flip a switch like that and what do i do i need to have a conversation with him to tie up loose ends hes been avoiding it but continually saying we will. what do i do pursue it or leave him alone until he comes to me for it. and why i just need some kind of reasoning because I cant wrap my head around how they work.