Muppitz, sometimes it can take several MONTHS to get back to normal - which feels like several lifetimes. I know cuz I've been there. I'm not a medical professional, but judging from my own experience (and that of a friend who faced a similar situation) I don't think your illness has inflicted permanent damage on your voice unless you have been giving it horrendous physical abuse as well. It sounds as though the effect the cold or infection had on your vocal cords is still in force (e.g. an excessive coating of phlegm, which is one of the body's defenses but feels like a strait-jacket). THEN they will need to heal from that, and the healing process itself takes time.

I had the same problems and suffered all the same feelings as you are going through, but hang in there and don't write your voice off. Do follow the good advice above about NOT STRAINING or trying to force anything, which will only make it worse and take longer. There's no real medicine you can buy for it, so just do all the common sense things and keep despair at bay by remembering that it can take a few months to come right - so don't try to monitor progress by days or even weeks or you'll make yourself crazy.

Your situation sounds very like mine (three times) and my friend's: and we're back to full strength. I really think you will too, so keep your spirits up!