Emotional abuse can leave scars that are very difficult to overcome. Its not something that happens over night and won't go away over night either.
She is coming to your place, and part of that should entail following the rules of your house. Given what you have told us, that is not likely to happen.
That being said, maybe this is a good time to stand up for yourself. We never get over wanting to be accepted in our parent's eyes, but at some point, we have to live our own lives. People who are abusive often are not that strong in their own right. Put your foot down. ie "this is what I am doing and the way I want to live and if you don't like it, you don't have to stay". I know that sounds harsh, an over time you have probably found it easier to give in than fight, but its time for you to live as you choose.
Give some serious thoughts about what you are willing to sacrifice. You might lose her innitially, but when she finds out that its either have a son or lose altogether, she may well go with the former. After I came out to my family, I lost my brother, whom I had been very close to before coming out, but he eventually got over it and we can talk again.
I think you will feel better if take charge of your life. Be polite about it, but firm. Good luck with what ever you decide and keep us informed.
sam1234