never, ever feel afraid of saying what you feel.
Go with your gut feeling and tell him. If he's any sort of father, he will realise YOU are his priority and get rid of this person.
deal with it. if interacting with her really bothers you, minimize the interaction.
just get ready to be 13
First I would change the age in your profile. :)
Second I would be honest with him but also let him know you are prepared to deal with it because it is not your relationship. He has every right to be happy.
Consider how you feel when your dad doesn't agree with someone you like. But this isn't the same because he is an adult and feels love differently than you do. Yours is still developing and you will likely go through several people as you discover who you are.
Is this you?
Depends on why I didn't like the person. If it's just personal taste, well, there isn't much I would be within my rights to do. I could tell him how I felt, but that's about it. He is the adult and has to make up his mind about that sort of thing.
Well you might as well tell him because he probably thinks this is good for your "friend"