She loved your Father enough to honor his last wishes. I'm sure she'll not force you to be like her, she is just afraid to be alone in this cruel world and that she loves you and want's you to be protected all the time.
I'm not justifying her actions but she didn't have any other choice to survive either, she didn't choose it, she had to do it. I know its hard to accept it but if you see from her perspective then she isn't the villain. I'm guessing she already feels guilty about having to survive this way.
Try reaching out to her, maybe don't agree with turning but atleast let her be in your life while she can.