I too was unceremoniously dumped, without explanation, a while back. What I learned is that I don’t “ own” anybody or anything in this life. It’s all lent to me.
Things can go sideways in many ways in this life. The sooner we learn to trust ourselves and take control of our thoughts, the sooner we will get through the grieving process. My ex showed no emotion whatsoever. Could care less if I lived or died. Some people can do that. So I finally was forced to care for myself.
What hurt more, and I need to remember this , is the death of people that truly loved me and would never have abandoned me. This will be painful, but is it worth the self inflicted wounds ? Crumbling to pieces over someone who obviously, for whatever reason, doesn’t want you anymore ?
We come in alone , and we leave alone in this life. Don’t ever put your heart in another humans hands. Learn how to live in the moment. Have gratitude for all the good moments you had in the past. For they are gone. Fill in this moment with not the content of past moments, but fill them with all that you can be grateful for right now. It will be difficult no doubt , but you can come out on the other side of this, probably better and stronger than before.
Best wishes.