Struggling through a thesis you're not enjoying would suck x_x
It did suck. I also had to change mentors ( or whatever they are called not that they mentored me much ) twice and my brother ( 15 back then ) almost died, midway through the thesis process. Luckily he's still around ❤️
Having to change mentors would be pretty disruptive. I had a mentor that I was worried abou at uni because they were an "interesting" lecturer (we didn't learn much from the lectures and basically ended up doing a lot of study on our own for that class) but was an amazing mentor.
Gah glad your brother survived, that would have been really traumatic D: