I not disabled, and I’ve had the same problems with HMO healthcare.
Those organizations drive decisions based on statistics, not the individual. I’ve seen my doctors working to find ways describe/categorize my problems so they could justify the treatment they felt was most appropriate (only after working through numerous doctors in the organization - one actually said “Well, I guess you’re just going to have to learn to live with the pain”).
Walking into an independent doctor office is completely different - they’re quick to work toward a solution, and move to a different approach when they see things aren’t improving. Because they don’t have to justify their actions to a risk/cost-management board.
Interestingly, the HMOs don’t hesitate to do surgeries. Never had any pushback there, even for things with moderate risk, but relatively low need.