I'm going to have to see a picture of the trombone project!
I was thinking.... don't try to connect him breaking things off with Helen with getting back together with you. Of course one has to happen before the other can, but they might not happen one right after the other. (Or at all, of course, but I don't want to be negative Nellie.) There could will be a fair amount of time in between. He may well question himself, and his ability to be in any relationship. Please don't get your hope too high that things will move quickly if they start moving!