Who am I suppose to live with.?

My boyfriend & I have been together for almost 9 months. We both really love each other, I’d die without him. We are both 14, so I can’t decide on who I’m allowed to live with. My mother has been in the hospital since the end of November of 2009. The doctors just told me like 3 days ago, she might not make it. My parents are divorced. My dad lives all the way across the country & I don’t want to have anything to do with him; he abused my mom & he’s a drug addict. I’d like to stay with my boyfriend, his parents don’t mind me being around him. Since my mom was in the hospital, I’ve been staying at his house, we’ve been sleeping in the same bed & everything. [Yes I am still a virgin.] I love him & I know he loves me; he takes care of me & I’ve never felt like this with anyone before. I can tell that he tries his best to take care of me; I think he does a great job at it. Not only is he my love, he’s my best friend. I can tell him everything. I also have a little brother, he’s been staying at his friend’s house, he’s 13; I love my brother very much too, he’s like my 2nd best friend. There’s only a couple of ways I can stay here legally:

1. If I’m pregnant.
2. If my brother gets his girlfriend pregnant.
3. If my mom lives.
4. Foster families.

I woulden’t mind loosing my virginity to him, but I don’t want to have a kid, he would get in so much trouble. What do I do.? Please help me.):