One can argue it was OP's mistake to not hire a few people himself, train them and delegate part of his responsibilities to them. This way he would have the man

One can argue it was OP's mistake to not hire a few people himself, train them and delegate part of his responsibilities to them. This way he would have the management position he desired, he wouldn't have to work such long hours, taking a medical leave would not be a big problem, etc. Instead he left the responsibly to build a team to someone else and not that surprisingly was left out of the loop.