I can see that it's very hard to let something go when there is nothing else to turn to.
I don't know how old you are, but where do you want to be in five years? Do you still want to be in this situation?
The fact is, you are allowing a situation to continue that you can sense is potentially harmful to you.
The longer this continues, the deeper the habit will be ingrained. The harder it will be to put an end to it.
So think ahead five years.
I have a friend who is still emotionally bound to a man whose relationship with her ended several years ago. They are still in regular contact. She sees other people, but the moment they try to get close to her, she runs a mile.
Yes, you have a link with this man. Is he the only man in the world you could have such a link with? I doubt it.
You say that you get exasperated with others when they don't 'get' you like this man does. But how do you think a person comes to understand you?
It's not magic. It comes from spending time together, communicating, talking into the early hours . . . you have to invest time and energy into a relationship to get that kind of connection.
While you continue pouring all your energy into this friendship, you're not going to be able to spend it anywhere else, so of course no one will match up. All your wealth of care and focus is being lavished on this man.
If that's ok, then you may still be doing it in five years/ten years. It'll be more like an addiction than a master passion. If you don't want that, then something stronger than your feelings for this man has to take control. So what in you is stronger than those feelings?
What would you be advising a friend to do?
When you break off contact with him and you say you know he'll be back in touch, why does that mean you have to respond?
Can you bring yourself to change your email address and telephone numbers?
I hope you don't think that I am being insulting by saying any of these things. But it does seem to me to be a very dangerous situation - dangerous for your future happiness.