Gosh this sounds so familiar! Ever since I had my IUD (copper) put in I have been fighting BV again. When I first started treating myself at home I tried a Vitamin C tablet vaginally and it burned. I think I was just too sensitive from having the BV for so long (and the antibiotics made it worse and worse) that Vit C was too strong to start with.

I douched with straight Hydrogen Peroxide, off the shelf at the grocery store, not the food grade kind that you have to dilute to use. I did it using a large medicine syringe - in the shower - I would try to hold it in a while and then let it flush out. I found it nice, cool, and soothing actually. I would rinse until the bubbling stopped which told me the bad bacteria was flushed out. It immediately neutralizes the odor. There was once when I had rinsed 2-3 times a day for a couple days in a row that I got very very irritated and it burned and I stopped for a couple days and then cut back to only rinsing once daily.

That worked for short term -- after that I started doing the overnight Vitamin C treatment I've talked about and it didn't burn anymore at all.

I would also consider looking into the post on this thread about the Apple Cider Vinegar --- I haven't tried that method personally but I have heard so many good things about Apple Cider Vinegar and it is acidic, I can't see that any harm would come of trying it out.