Grad school SUCKS. I was diagnosed during grad school and remember working in the (chem) lab from 2-5am the first time I took Lamictal. I switched to taking it in the mornings, but man was that mad.

I really wish I had advice for you, but all I can say is that there's a whole world on the other side of grad school & bipolar! I stumbled my way through some SSRIs, Lamictal, and benzos, but it really wasn't until grad school was over (and other stuff in my life) that I was able to truly function again.