Not everyone is emotionally intuitive, not everyone can sense or anticipate another's needs, and being that unsure, probably makes them keep their distance, or do it because being alone is what they would prefer...

I too learned this lesson the hard way. That people can't smell what I need.

I'm very good at reading the room and figuring out what someone else needs, and I was mistaken when I believed everyone has that ability and much like you, ended up feeling alone and rejected.

I learned to ask for what I need i.e. in the event of this: I need you to ramp up the hugs and cuddles, arrange movie marathons as they're a good distraction, I should not be isolating too much, etc...

Not easy for me at all and I still struggle with it.

So sorry you're feeling so alone, but maybe elaborating is not such a bad idea, especially since your SO did express being unable to read your mind.