[NLY]

The commonly known problem is that as the use of antibiotics becomes more and more widespread, the bacteria become more and more resistant. This is especially common when people quit their antibiotics prescription halfway through because they "feel fine"; some of the surviving bacteria then mutate into more resistant strains.

I don't think you're doctor should of prescribed two years worth use of antibiotics, most acne medicine (oral) are submitted to a 6 months period in which you discontinue use. Although I'm not a health professional, I would recommend possibly reducing dosage if you wish to stop treatment of cephalexin. (maybe one pill everyday instead of two that way it's easy for your body to adjust to the changes)

Another thing I would recommend is to get your general practice to refer you to a dermatologist (specialist in skin) and they can find alternatives (topical treatments) to your situation.