Sounds like a condition called Hidradenitis Supportiva. I have suffered with it for years. It is a difficult condition to treat. I have found that not smoking, wearing cotten underwear and avoiding tight fitting pants have helps. I did have 14 cm x 3 cm of skin and small cyst removed from my left groin.
I am not a doctor, just a consumer.
From the symptoms they sound like hidradenitis suppurativa. Hidradenitis suppurativa is a skin disease that affects areas bearing apocrine sweat glands and hair follicles; such as the underarms, groin and buttocks esp in women.
Apply warm compresses on the lumps and keep the area clean. Topical antiseptic treatment and topical antibiotics such as mupirocin or neomycin containing ointment is very useful. If still the lumps persist then specific treatment like antibiotics, vit A supplements, corticosteroid injections, isotretinoin, antiandrogens and sometimes excision and drainage , laser therapy and radiotherapy are found useful. I feel that you should consult a dermatologist and discuss these options with him.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.