I haven't been able to travel on longer flights in years without being able to put up my feet due to a medical issue. So I plan for business class fares at a minimum and look for deals to make it possible. Or I don't go. Am I upset that I have to pay for business class and economy isn't a choice? No. I save getting upset for when the wheelchair doesn't show up to take me to my gate and I risk missing my flight.

To the OP please stick around and use the resource that is FT to help you find ways to limit your costs and make travel more likely to be possible. It may be through credit cards or miles, sales, or tricks such as changing your departure airport or moving your dates a bit. On the whole I find people helpful to those that want to learn.