You are not nuts at all. I have felt the same way, often. I have held off telling a lot of people, not for any reason other than I can't stand their excitement - I just can't share it with them, I'm not feeling it yet.

If you have anyone you can talk to about this, I recommend you do it. Even if you blog your thoughts here on BB for a bit, so others can share with you, and you won't feel so weird. I'm sure lots of others will have some great ideas on how to help bond with your baby.