I feel for you, I really do.
The problem with JW as a whole, is that the religion teaches you to be codependent. Free thought is discouraged, and the only answers are from the WTBTS. Now you have been out, even though it has been a while, you still struggle with the idea that you can make decisions for yourself. You expect repercussions. These feelings are proof alone that Jehovah's Witnesses are a mind controlling cult.
I too have had to think long and hard about what this means to me. I suggest that if your anxiety is so bad, perhaps you really should see a counsellor, as those guys are trained to deal with such debilitating religions and their effects. Maybe read up on codependency. TALK to your boyfriend. While he may not fully understand, he no doubt would love to hear about it, and provide you with loving support.
Just remember this - Sin is a social construct. You WERE NOT BORN INHERENTLY EVIL. You are a loving, kind person, do not allow anyone to tell you are evil, or a sinner. You are innately good, as you no doubt feel and know when you are not facing these anxiety attacks.