They abstain because they have made peace with Israel and they don't want war. Punishing 2.2M people, for a terror group's activities is collective punishment and a war crime.
They have razed 25% of Gaza to the ground. That is neither minimal, nor collateral damage. When I initially supported military action I was hoping for it to end within 2 weeks, but as you can clearly see, they don't give a shit about the Palestinians or how many of them die. Their end goal is probably to use this as a reason to steal more land - I think one of the politicians or generals said, "Gaza needs to be smaller than before". Also, an Israeli politician last week said that "nuking Gaza is an option". Does any of that seem careful to you?
So what? Why not? Why not give a shit? You have 'superior moral standards' right? You are from the 'civilized, free world' after all. So why not give a shit about all of them without worrying about what Muslims give a shit about? Is your argument, "Meh, 300K Muslims died in Yemen. 10K in Gaza is nothing." - because that would show you have even lower standards than the guys responsible for all those other deaths. And if that is the case, then okay. We don't have anything else to talk about because it is solely your problem.