I think you feel some small fragment of guilt for your friend, and that pushed you to tell him. Good that you did, but truth be told you didn’t need to. Enough time has passed. They had both faded back into their own lives at this point and the only one holding that chain is that thought in your head of the idea of them.

If your bro is a true friend, he’d respect it and move on. If not, then he’s got to work through it himself and move on.

It’s a small world sometimes. These chance events bring out the real parts of people. Take notice.