This is great, congrats! How did you get your first few customers? How do you plan on monetizing? I realize Peergrade is free, but, as an educator, do you have any advice with respect to selling into K-12 vs higher-ed?
I was in a very similar situation 6 months ago. If you have a typical agreement in place (4 yr vesting schedule w/ an initial 1 yr cliff), about 10% is not only reasonable, it's what you're legally entitled to. If you're legally entitled to 10% and you believe the company is going to increase in value and eventually exit without you, it would be foolish to sell then your stake.
It'd be interesting to see if there's a seasonal correlation here - since most of our vitamin D comes from the sun, expectant moms are probably more deficient in the winter. Wonder if third trimester during those months, when there's rapid neurogenesis, leads to an even higher incidence of these traits.
I noticed you posted Launchaco a few months ago. Why do you think this post succeeded in generating traction while the previous failed? Love the product!
"Because of the API TOS, we couldn't really tell anyone how to use it, which made online marketing very difficult." - Can you say more about this? What were you doing that violated the TOS?
You can't deliver on your mission of democratizing education or operate as a VC backed business (which enables these attempts in the first place), if you're not making moves toward profitability. These companies are pioneering a space and searching for a viable business model in the process. They're surviving.
Something like this: https://github.com/IBM/MicroscoPy
What you're describing sounds like it could be more than burnout though. I would also try to find someone to talk to.