Have you ever been checked for hpv, human papilloma virus?
To my understanding, hpv is notorious for causing bacterial vaginosis.
It sounds like you might have b/v. Hpv can cause vaginosis or vaginitis with vaginal discharge, and vulvar pain and itching.
It might not be hpv, but it very well possible, could be b/v. I would recommend a clinic check up, and if you have it, it is easy to get rid of with medication. Good luck!