My job requires me to deal with clients everyday. After almost 5 years, I learned to be plastic to them!
Especially demanding clients like doctors. Trick is, just give to them what they want. mas maging makulit ka than them. Always smile (eventhough deep inside inis na inis ka na) then don't say No.
Tell them I'll get back to your or we'll try our best. Rant all you want in the office so you could release the tension. Don't take things personally. Work is work. When I was 1-2 years in the industry, super iyak pa ko after work because this client/guest/boss blah blah... but now, deadma! Pasok dito labas sa kabilang ears. I'll just do my best if it works great, if not.. move on.