@your rep comment,
Yes I think that is part of it, though this emotional stuffing and shutting down started occuring when I was around 17/18. I know the source of it- I told my friends in high school that I was very depressed and contemplating suicide and although I was crying and clearly in distress none of them stayed with me to talk to me about it. So I decided from that moment on I'd never speak to anyone about how I felt again. So I internalized everything.
That was just compounded by what I went through with my ex and other "relationships" I had in the past. I was seeing a therapist for a few months earlier this year and it has helped a great deal, but it is still a struggle.