It would be very difficult to "talk" some one through this.
The voices could be anything really.
Thoughts that you actually have about yourself,
thoughts you are "picking" up from around up
or something that someone is thinking and you can feel that.
Be careful about who you go to, I feel a really good spiritual counseller, someone in your church, or group, maybe a trusted friend has a "understanding" mother, someone, who could help you initially understand what it could be.
Are you "down" on yourself.
Your surroundings don't sound helpful.
Is this how your father talks to you.
Is it all the time, that may be a clue as to where it is coming from.
The "veil" between this world and the next is easily penetrated.
Are you taking drugs, or have you in the past, this makes one much more vulnerable to this sort of communication.
It is real to you, and you want it to stop. have you told them to stop, what happens then.
Does it ever stop, when is this.
Sit in a church and see if it still happens.
This knowledge about it will help you be more in control, when you do "get" some "professional" help.
I say again be careful, make sure you are looking after yourself, and are in nurturing relationships.
If you want to contact me, and answer some of these questions that would be good.
Take control back of your life.
I hope to have been of some help to you