Hey....Wow I wish I had come on sooner. I suffered from severe perioral dermatitis in late 2012. It was horrible, trust me, I believe you. Mine started from using a steroid cream, mainly because my skin became addicted to it. (prescribed by my family doctor to treat a small rash)
As soon as I stopped, it exploded on almost my entire face. red, itchy, burning and ugly.
Heres what I did...mind you it took 3 weeks, BUT..knock on wood, I haven't had it since.
I bought ORGANIC apple cidar vinegar(braggs brand)
I diluted it about 50% with water and used a cloth to gently wipe it on my face twice a day.
I also took a table spoon pure once a day.
I was on minocycline antibiotics for 4 weeks which seemed to help as well.
I also used a cream (prescription) called METROGEL.
This was simply amazing.
I also learned to stay away from products containing SLS (Sodium Lauyrl Sulfate) as it will just irritate your skin and may cause another outbreak.
I use AVEENO foaming wash for my face. As well as AVEENO shampoo both which are SLS free.
My toothpaste is SLS free as well.
I also restrained from touching the rash or wearing any makeup to cover it. Don't pop them, they will spread.
After I actually went on Accutane because I found I couldn't use acne creams anymore.
And that seemed to work for me nothing for years.
Good luck, feel free to PM if you want with more questions!