Update

[AntoniaB]

I haven't been through a situation like this at all, but it seems to me that you're doing well with when you are choosing to respond, and you're giving him the opportunity to lean on someone else besides you but also being "there" or responding for the most important things he has contacted you about. I think you're doing well, especially with the fact that you're finding that your own activities are "less boring" than the dynamic that's been going on with him.