Tamar Braxton Says She Almost Died, Woke Up in Pool of Blood

Tamar Braxton says she very nearly died this weekend ... explaining her friend found her in a pool of her own blood -- and, she says she doesn't know what happened.

The singer-songwriter posted about the harrowing experience on her Instagram Stories Tuesday ... admitting she struggled to write the news -- but she feels she needs to tell the whole wide world about what happened because people keep calling her and asking.

On Sunday, Tamar says, she almost died ... saying she was found lying in "a pool of blood from my friend with a face injury." She says the injury has worsened over the last few days.

Braxton says she fractured her nose, lost a few teeth and is having a hard time moving around. Her perspective on life is different, too now, she adds.

Scariest of all, Braxton says she doesn't know what happened to her ... so, it's completely unclear how she suffered her serious injuries. We've reached out to Tamar ... so far, no word back.

Braxton has dealt with numerous health issues over the years ... withdrawing from "Dancing with the Stars" due to pulmonary emboli in her lungs. She's also struggled with mental health issues over the years.