Space travel is a meme. It won't be like Star Trek. You're stuck in a pressurized can with some other assholes for years. You all could die from sudden depressurization at any moment. No fresh air or water for bathing, so it smells like the worst sewer in India forever. There's nothing to really do so you slowly go crazy from cabin fever. Once you get to your destination, say Mars, again you are stuck in a pressurized can on the surface with all the same problems on the spaceship, no fresh air, no escape from your other crew members, if one of them goes crazy the only thing you can realistically do is kill them to save yourselves. It would be like being in prison but without the benefit of going out in the yard for fresh air and sun, it would be Hell.