Couple months ago I lost my best friend but it wasn't that she felt like she wanted to see less of me, it's that she never wanted to see me again, period. It was at that point that I remembered all these times I shook off when she wasn't exactly really a friend. When she left, I cried and cried and didn't really want to be alive anymore (I still don't but for different reasons). Though in the "end", even though I still miss her despite all her crap, I am still here somehow and it doesn't hurt like it once did.
As the saying goes: "this too shall pass".
I agree with the other people on advice: let her be. If she comes back great, if not that sucks. In the mean time I got through my loss by crying it all out and then working on a lot of projects which had their own headaches to keep me busy. Maybe you could try that. Just try to push through this initial phase. It gets easier.
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"Sometimes I've believed as many as six impossible things before breakfast."
Your neurodiverse (Aspie) score: 175 of 200
Your neurotypical (non-autistic) score: 37 of 200
You are very likely neurodiverse (Aspie)