I have a blushing problem as well. I don't do it all the time, it just comes on in certian situations and makes me feel like a freak.
I tried explaining to a couple of people and the responses I got were useless, kind of in the "just get over it" line. Nobody seemed to understand and nothing I read ever indicated that anyone else had the same problem as me. After putting up with it for years, and having it really destroy my confidence, I went to my doctor and finally said "I have a problem with blushing". I told her that I was interfering with my life and that it was probably the reason that I have never had a boyfriend.
She immediately said that she thought cognitive behavioural therapy would help and gave me a referral to a psychologist.
After a couple of sessions with the psychologist (and some independant research of my own - see link below for my recommended book), I realised that both the doctor and psychologist had immediately recognised my problem for what it really was - the most obvious symptom of my social anxiety problem. I couldn't believe that after years of treatment for mental health problems, I had finally either asked the right question, or met the right professional, and somebody actually understood what I was saying.
It isn't going to go away magically, but I'm working through the book and having sessions with the psychologist and I'm feeling quite positive really.