I can't be vaccinated, so I need to rely on herd immunity instead. So at what point does your right to avoid vaccinations end, and my right to avoid the unvaccinated begin?
It ends at the point that you force someone else to have a medical procedure for your benefit. Anti-vaxxers are ignorant idiots but you do not cure ignorance or stupidity by making it illegal (tempting though that is)...you cure it through education. However the ironic thing about this law is that it encourages these idiots to home school their kids where they will be able to propagate their ignorance to the next generation.
The moment you force people to have medical procedure you are on a very slippery slope. Vaccines are incredibly safe but there is no zero risk medical procedure: one in every N million vaccines will produce severe complications and sometimes even death. So, to flip the argument around, how many people's lives is it fair to risk to reduce the risk to yourself? Now I realize that this is not entirely fair since, by not having the vaccine the risk if they catch the disease it prevents is far higher but the fact that either way there is some risk means that the proper solution is to educate people about the risks and then let them make their own decision which, will hopefully be to get vaccinated. If not then why stop at forcing vaccinations? Think how many lives could be saved by forced live kidney and liver donation!