Lucky, I can totally sympathize with you here. I have the same problem you do, I bottle everything in, so much so that at one point in time, I only felt anger or nothing (ie: normal)
I'm not sure what will work for you. Having my son helped me tremendously. That little bundle of helpless wrinkles that needed me totally undid whatever walls I had built up. I think a large part of it was that unconditional love that a child gives. (I am NOT saying to go out and have a baby lol, just thought I'd clarify that)
I STILL have to work on expressing myself to others, and I rarely cry unless I'm extremely angry.
It sounds as if you have someone there who is willing to help you and may stand by you through it all. I wish you all the 'luck' in the world on this journey. It's not going to be easy but it will be worth it.