According to the above article from CNS News, "the RIGHT news, RIGHT now," that's 1 in 4 doctors, the rest pursuing their profession and putting first their oaths to provide care for those in need.
One of the main reasons cited in "the right news" article is that some insured under the ACA have high deductibles and doctors are afraid they might not get paid. For one, that possibility always existed, not to mention the fact that many sought and received treatment in emergency rooms without ANY insurance at ALL. So what's the difference??
Bottom line is, if your doctor is opting out of Obamacare, then maybe you've been seeing the wrong doctor.