I'm familiar with First-Past-The-Post voting and the spoiler effect. I'm also familiar with choosing to vote for whom you'd prefer to fight when elected. We are dealing with the crimes of crimes here and I can absolutely understand anyone whose family is affected to not want to take an active role in their killing. Especially since the campaign has not signaled to that voter block, that they are seen or heard. The best example is denying a Palestinian-American a shortened and cleared speech at the DNC. It could have been only a ceremonial thing, less weight than lip-service, but they opted for exclusion instead, i.e. the opposite.
My main point though: How can this party not be clearly ahead of that menace to democracy and its institutions? This one voter block should not be the deciding thing. Overlooking the agency of the Democratic Party in this and putting full blame on the people rubs me very anti-democratic. Implying them to be immature and other forms of voter shaming is not making a good case either.
Look, I get what you are saying and even agree to a certain degree. Yet, the premise here is that one of both parties is opposed to genocide, which is false. For the affected voter group, who are getting shamed for making the crime of crimes their litmus test, both people are trying to make more holes albeit of different sizes.
So, what would you do? I would probably throw both of them over board ;)