Symptoms come and go in cycles and flare-ups are common. There are triggers that cause trouble are first cosmetics, shaving creams, after shave lotions, and all compounds that contain alcohol or irritants. Different people have different triggers of flare-ups. These include hot drinks, stress, alcohol, sunlight, spicy foods, extreme heat or cold. A diary is useful to pinpoint your triggers.
Men do best with an electric shaver.
First see a dermatologist. They know what to do. The metronidazole is active against the demodex as well as many bacteria. The worst can be covered by make up until it comes under control. Topical steroids may help.