Sorry that your mom is being so horrible to you. The things she said must have just ripped out your heart. You shouldn't have to defend who you are. You were being honest with yourself and with them - she would have have liked it better for you to live a lie and be someone you are not - that makes you the better person in the end.
However, I think you are better off to put some distance between you and the family if this is how they are going to treat you. Nobody needs to be demeaned and belittled the way she did to you. The family members who can accept you for who you are will keep in touch with you. Leave the door open to them and even to your mom if she decides one day to soften her position toward you.
Part of this reaction, aside from the JW slant that teaches them that this is a 'choice' that you've made, is the part of her that is screaming to her that she is responsible for you being this way, that somehow she is at fault - whether biologically or in your upbringing or a combination of the two.
This is advice for down the road a little ways, but you need to do this at some point to legally protect yourself and a future life partner and any assets you acquire together from people who are related to you, but who treat you with the contempt your mother has demonstrated. Don't think for a second that your JW relatives who won't give you the time of day right now won't turn into vultures and try to glom onto your estate in the event that you pass away. Prepare a Will and update it regularly. You may not have very much now, but you may someday own a house and a car and a business and so on, that you may want to bequeath to your partner, and not your JW relatives. It may not be a priority today, but keep it in mind for the future. Protect yourself.