Your letter WAS a jolt of reality, and you said things well. I think it was all very reasonable requests.
The problem, as I see it, is rather than let him STEW on that, and on the consequences of his own actions, you then RESCUED him with your friendly text messages, the massage, etc.
Your e-mail put him into his crucible. Let him stay in there now, and please only communicate about the kids and finances.