Hello and welcome. If talking to people on this board and reading the books that Mr. Flipper recommends, doesn't help, you may want to see a therapist. Being in the jw organization at any age is emotionally abusive, but it is particularly bad for young people. Your parents probably realized that on some level, and that's why they wouldn't allow you to get baptized. But then when they learned that you were somewhat sexually active, they flipped out. That's normal for some parents. They probably pushed you to go back to the meetings, because they didn't know what else to do, figuring you may stay out of trouble if you continued with your study, meeting attendance and field service. At your age it may be difficult to realize that parents are just people. They don't always have all of the right answers and then become frightened of it.
Just take a deep breath and keep reading and posting here. Things will probably get much better for you in time. You may also want to have your boyfriend read and post here as well, so he can get an idea of what you've been through. While reading your post I was reminded of this YouTube video I saw just the other day. Listen and see what you think.
Hope to hear from you again soon. You and your boyfriend sound like very nice people, and you have nothing to be ashamed of. Take care. Good luck and God bless.