Another thought for you....

Which could be completely off the mark, but haven't you said in the past that you consider yourself codependent? Codependents have the compulsion to help and fix other people- it's our jam and we feel really good when we're engaged in that. Is it possible that you're feeling something like that?

It can be a pretty strong drive to want to help someone, especially when you feel like you know what it is they need- which is often the case with someone you have a long term bond with.