Could it be possible that the yeast infection is an allergic reaction to something?
Allergic reactions (contact) of the vaginal or vulvar epithelium are often confused with yeast infections because they cause a histamine release in the skin of the vulva with subsequent itching or burning.
That is one reason why culture for yeast is so important because you may assume it's a yeast infection when in fact it is allergic. The most common allergens are feminine hygiene sprays, contraceptive foam and jelly, even carrying agents in anti-yeast preparations, lubricants on condoms, or soaps or bath oils.
It doesn't sound as if these are a problem in your case but you have to be your own detective with allergens. The fact you are sensitive to terazole does make allergy more likely.
Are there any other things I can try or am I just "doomed" to take yeast infection medication on a regular basis for the rest of my life?
Make sure this is yeast. Sometimes women with sensitive skin will react to any normal vaginal secretions when they get on the vulva because the secretions are naturally acidic.
You can try petrolatum jelly (Vaseline) to coat the vulva (a small layer) to protect it from acidic discharge or you can use a tampon to block the discharge from getting to the vulva and irritating it.
These would be tests to see if it is just an acidic (but normal) discharge you are reacting to or a yeast infection. These things will usually not prevent the reaction to a yeast infection.
Could it help to stop taking the pill?
Some women will get more yeast infections on certain birth control pills. I think it has to do with the specific progestogen in the pill. I would suspect that Levelen would be worse than Ortho Tricyclen because it has a stronger progestogen than Ortho- Tricyclen.
Sometimes when we have women discontinue pills, a recurrent yeast infection gets better; other times there is no difference in the rate of infection. It would take a 3-month trial off of the pills to tell.
Boric acid as treatment for recurring yeast infections
What about boric acid?
Boric acid vaginal suppositories have been used in the past for resistant, recurrent yeast infections. Many experts in vaginitis clinics use them still.
Unfortunately in the U.S. we don't have any commercial vaginal suppositories with boric acid. Perhaps in Europe there are some if that's where you are. We have to have the pharmacist mix them up. Find an experienced pharmacist who remembers the formulation.