I can see how that might be an adjustment for you. I got very into Fruits Basket earlier this year, and I still enjoy it, to the point that I had to seriously debate whether or not to buy a Furuba calendar or wait for the one for GoF. (I bought it and decided I can have two calendars this year.)

I'm willing to bet that seeing the new movie will revive your interest in HP (unless it really really sucks), but you'll still pursue your other fandom(s).