I haven’t read all the posts, but I just thought I would chime in.
I was raised very Protestant, by a very strict Protestant father. My mom is also Protestant but was Catholic (non-practicing) as a child.
I will say that when I told my dad about my plans to become Catholic, he was very very upset with me. I think he was very angry and didn’t understand. It’s unfortunate how many Protestants feel the need to show hatred to Catholicism when they really don’t understand. There are so many lies and misconceptions out there about Catholicism.
I do have to agree that you may need to wait until you are a legal adult to become Catholic, just for the fact that you are living with her yet. But this wouldn’t stop you from learning more about the Catholic faith during this time. Order some Catholic books, continue to post of the forums, etc.
So I’m not sure that my post really helped, but just know that in your struggle, you are far from alone. Many of us converts have also had a rough road home.
So hang in there!