Being supportive is hard when you don't agree with what you are supposed to be supporting. I have a really hard time with doing this. How am I supposed to cheer you on and wish great things for you, when I believe your doing the wrong thing? I just can't bring myself to this place. So instead I say nothing, you know that old adage that our mom's all taught us "if you don't have something nice to say then say nothing" that's what I do and THAT get's me into trouble as well.
Whatever it's your life I really could care less what you do, but don't expect me to be all happy for you. Sometimes whether you realize it or not the best support is the support you don't get. :-)