I suffered through a major first Grovers flare up right before Covid-19 lockdown and when I was finally able to see a doctor in person and had a biopsy taken I was diagnosed with Grover Disease. I am 38 and female.
I know we are all so different so one cure may work for one but not the other but I have found Homeopathy for me has been my saviour. I have a bottle of Homeopathy Natrum Muriaticum 30c tablets with me at all times. I take the Chronic dose three times daily but if I have a flare up (from getting hot and thus sweating) I take the Acute dose (see bottle for full instructions)
I have found that Grovers flare-ups happen when I get hot and sweat forms on my skin and then dries, I feel a strange stingy feeling on my skin when sweat is drying and a flare-up is happening. I can still exercise and get hot etc but I always make sure I shower as soon as possible before the sweat dries on my skin. if I can't get to a shower and the sweat dries on my skin I will have a flare-up.
Ice is also a good way to catch a flare-up and stop it from going from a mild flare-up to a major one. if you catch a flare-up at the early stages it will be gone within hours or max a few days.