I am sorry to hear that you are in this difficult situation.
Your first step would be to demand a paternity test.
If you cannot get her to agree a court will order it
If the child is your child then you will have to pay child support if the child lives with the mother.
In terms of custody and access, your rights are the same as hers.
But even though she is a disgusting person she won't lose custody of the child unless this affects her parenting.
So it may be that you will be looking at joint custody.
Your best next step would be to retain a family lawyer.
Does that help as a starting point?
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