Yes, I would go back to Vagifem, and do the 2 or 3 week loading dose. Ovestin is great for those who can use it, but I'm one of those who can't as I react to it, maybe you're the same. This whole business is enough to give anyone a headache, it is very stressful until you get it under control.
As a barrier and moisturizer, how about trying an oil-based one, such as Yes oil based. Olive & Bee is also very good, just olive oil and beeswax.
It all takes time I'm afraid!
Best wishes,
JP x