A milky, odorless discharge is more typical of herpes, but this is not a hard and fast rule.
The doctor may have checked for all of this already, but here's the usual starting point:
1. Other STDs.
3. Bacterial vaginitis (which often has a noticeable odor, but might not)
4. Group B Strep (lots of women have this and are symptom free, but it an be troublesome for some)
As a note Baterial vaginitis and Group B Strep are both notoriously pesky things to get under control and an take a few rounds of treatment to get under control.
You may be in some sort of a viscious cycle, where maybe it starts with your yeast flaring up, which in turn triggers a herpes OB and then the yeast flares again (rince, lather, repeat). If treating for yeast seems to help, it's okay to take you antivirals at the same time. This same sort of visious cycle could involve not just yeast, but BV, GBS, or some combination of the three.
The next time this starts to flare, see what you can do about getting swabs done before you treat for anything to see if something else comes back positive on the test.
When Grace / Lenore come along they may have some more suggestions on what may be happening or what to ask your physician for.
Hoe eet jy 'n olifant? Bietjie vir bietjie.
(Translation from Afrikans: How do you eat an elephant? Bit by bit.)