There are people out there voluntarily going through experiments on what it would be like to endure the stress of long missions in enclosed environments preparatory to one day going beyond our own terra-system. Jocelyn Dunn is one of them, and PopSci has an interview:
Were there any particularly challenging moments?
Somewhere in the second half of the mission we had a power-system failure. There hadn’t been any sun for a week so our solar-energy setup wasn’t helping, the hydrogen backup was running low, and the gas generator wouldn’t charge the batteries we needed to run the critical systems. In a real Mars mission, that would mean your life support is failing. We needed power to run our labs, not provide our oxygen. We felt stressed, but imagine how magnified that stress would be if you lost power on Mars.
I have to wonder how I would fare in such a situation. I watch movies like Apollo 13 and see how confined their space was and I have to wonder if I wouldn’t eventually just completely wig out. This is probably why I explore other worlds through writing. It’s safer for everyone involved.