I'm glad to hear you have a counsellor, I would have suggested talking to one if you hadn't already. Sexual abuse of any kind is horrific and inexcusable, the fact it was his own daughter makes it even more monsterous. It's good to hear that you have thought it through and are set on going down to the police station. Don't start getting second thoughts when it comes closer to the time.
Unfortunately you will have to see your dad again after you've turned him in. You will need to testify against him and depending on how the case goes, you may need to be in the same courtroom as him while doing so.
It sounds selfish, but it is time you started thinking about yourself. Yes it would tear the family apart, but for a good reason. If it was menial I would say don't bother, but this is a big deal and he can not go unpunished. Think about all the people who have been in similar situations and are too scared to come forward. You need to do it not only for yourself, but as a message to everyone like your dad - they CAN NOT get away with it.
It's not over yet, and unfortunately won't be for a little while, but it will be eventually. PM me if you want to talk.