I can feel your crushed spirit... I'm sorry for your pain.
5 years ago my wife put an end to a relationship that meant a great deal to me. I love my wife and want to be with her, so I had to let this be even though it sent me into a deep, dark place.
While time heals to a degree, 5 years later I am still sad. In some ways it feels worse than a death. With a death you have no choice but to eventually move on because the person no longer is on this earth. But in yours and my situation you know that the person is still alive and you still care for them, but cannot have contact. That makes the process of letting go and moving on so much harder...
My hope is that you find at least some comfort to help you keep going...