Face rashes; red, dark & white spots.

Previously i had itchy rashes on my face; detected as Seborrheic Dermatitis by one of your doctors. I got cured with the medication, but as soon as I stopped it, which was after its one week course completion as suggested by the doctor, the condition reoccured little differently. I now have red dry rashes and acne kind of thing on my face which burns when I sweat, there are scaly dark patches in some areas and few white spots too. Out of the doctor's prescription, I have been taking all the prescribed medicines (Acemoist cream, Cetaphil gentle face cleanser and dosetil cream) except the oral tablets (xyzal) since this second occurrence (which is going to be a month now) in the hope that it will work, but it only brings it down a bit and doesn't eradicate it. I don't want to always be on medication so please help me cure it from its roots; let me know its causes, so that I can take precautions.