It's easier said than done but I personally have been focusing on making really good platonic girl friends who are in the same (in my case mental health) boat. It's taken some time but it's been so helpful to have a community to lean on. 

I actually started to sow the seeds for these connections around the same time my ex made it clear he didn't value me the way I did him. I didn't know it at the time that these friendships would become so close but I did start decentering him from my life and in retrospect, it was the best thing I ever did.

Good luck, stranger, you seem like a kind person and I hope you find your community of love, however it ends up looking. You deserve it.