First of all, are you me? I honestly identify with everything you've written. So much so, I could have written it. I'm about your age, 17. I started figuring out my mother when I was 16 too, and I ran away right before I turned 17. (Only to be greeted upon return with "you made ME look like such a bad parent for what YOU did", of course.) When I returned, I was also taken to multiple doctors for STD,pregnancy,and drug testing. Even when everything came back clear/negative(even with full on blood tests), she told me that I am still pregnant and it hadn't been enough time between tests and the last time I had sex.
Not long after, I injured myself at work and they fired me for it(pending lawsuit, no worries). Afterwards i slipped into a really deep depression and slept too much or too little, didn't want to get up to do chores of any kind, and I had a thumb spica brace for 2 months. I still continue to be told I'm lazy and unmotivated and I'm wasting my life. I'm at the point where I do not care at /All/ what she threatens me with, says to me, or tells me to do. I find ways around all of it. I am close to 18, I am taking my independence.
She took my phone, I went to walmart and got my own. It pissed her off, but I don't care. She took my car keys? Cool, I can get active and ride my bike where I need. I don't answer the phone when she calls, and I'm pretty much doing what I want at this point. I don't let her offer to buy me anything(it'll have strings attached). She has nothing to hold against me or above me at this point. My car is under my stepfathers name.
I gave her my old phone that still had service, and a message from my stepfather came in about my mom being "deranged". Him and I are through with her crap. Anyway, she called him while we were out at dinner and told him to pack his stuff and leave because she wasn't going to be treated like that. The next morning she came into my room and told me "What you choose to do it up to you, I don't care. Go live where you want." I don't know if it's another way for her to make me complacent or not either.
I understand what you're going through. I have no where to go, however. If I were you, I'd pack my things and go live with my boyfriends family. Work on getting yourself a job so you can contribute towards groceries and other little expenses so it will help you feel like less of a burden. If they're offering you their house, they won't think of you as a burden. You'll be surprised at how you make a total 360 within a few days of just being away from her. You'll experience what being happy is like. I'm at the bit waiting for my 18th birthday so I can split asap.
Oh, another note. Don't let your mom guilt you about your sexuality. That is your personal information and you have no obligation to tell her anything. In my case, I know my mom is the last person who can talk bad about me for having sex, she's not the saint she fronts as.
If you want to talk, sendm e a message. Good luck.