Why was it extremely unhealthy? The work load? The lack of sleep with work, kids, and school? Asking because I’m sorta in the same position

Specifically CS7210 is demanding because of its assignments. The assignments come from UW's CSE452, have very little direct connection with the course lectures, and require you to implement a Paxos-like system correctly, basically in one shot, in an environment that is very difficult to debug. So the projects turn into 60-80-hour slogs where students change parameters semi-randomly until something starts working. CS7210 shares that aspect with a number of other courses in the program.