I like to remember that time is on your side, it will get easier as time goes by just for nature of it. So focusing on going through the day-to-day the best you can while being kind to yourself and letting the days past is what helped me.
It’s not easy, you have to go through the grief to come up on the other side.
But stick with the things that make your present more bearable and you WILL come up on the other side.
For me it was doing things for myself: listening to music, visiting close friends, cooking for myself, going on walks on nature, spending time alone and bored and finding new things I liked and enjoying my own company was life changing.
The loneliness is rough but it can be a great teacher (at least I like to think something had to come out of all that pain).
I guess it really depends on the break up the narratives you are telling yourself right now, but if you can be mindful about them, observe them, and let go of trying to understand and control everything they get less cruel. Right now you just need to survive and receive some kindness, later on you can build the story around it (Without the fog of the pain around it).
And for the love of god cut contact with them, their family and friends, at least for a while. rebuild yourself outside their zone of influence. Show vulnerability if you can, it can bring great support and lending ears, BE KIND TO YOURSELF (although have in mind sometimes over indulgence is not kind).
You will get through it, time is on your side.
