Did you ever ask him if he felt anything similar as you did?
I cant say why or what is happening to you with all this. You said that "Sam" stopped entering your dreams for a while, and that lead you to beginning to think of him again. So since you seem to have a very unique connection to eachother. Then this curiosity of yours, that made you thinking of him again might have reached through to him. So it could be that he goes through the very same problem that you do, since you might share this special ability from the begining of it.
Im not saying that you two actually or abolutely ARE connected in any way as you describe it. But I definitely doesn't rule out that possibility in your story.
Here however is some suggestions of what you could try to do, to stop "Sam" from entering your dreams. First of all, I would say that you need to stop thinking of him if that is a possibility for you. It could be that you just recreate your strong memorys of him, along with the curiosity of your special ability that is a connected memory of him aswell. And that would most likely create a pretty strong impression on your mind I can imagine. Which could be the reason why you keep see him in your dreams. So if you can stop thinking of him and what you two seemed to share togheter. Then let a week pass by, only to check if you have any recall of him in your dreams when the week has passed.
If he stil appear in your dreams after that, then simply try to ask him what he wants. Or set your inner intention to a feeling that involves that you have now moved on with your life. And that you only are there merely to say good bye if you happen to see him.
I liked your story though, and it would be very cool if you actually share that bond that appear to be there. Any way, hope you will be able to solve your problem with this, or maybe develop it further if that is a option or possibility for you. Good luck to you!

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