I am having a super brainfart!
There's a word I'm thinking of, I've been trying to figure it out for a couple of days now. It's killing me! I tried googling definitions, looking in the dictionary and it's just not clicking!

I THINK the word starts with an A and has a similar meaning to empathy, I suppose?

It describes a relationship dynamic between people (Probably only two people). Where, they are... linked? Or connected in a way? Maybe spiritually? They feel each other's emotions, maybe their pain as well. 

I'm thinking like... twins? The might have this sort of strange connection, because they feel one another even if they're apart. 

Any clue?