But if you have kids and want to kill yourself, I think that's simply not ethical. As if it wasn't enough to have brought them into a world where suffering is so commonplace, now you want to scar them forever by committing suicide. They had no say in this matter, you brought them here out of your own volition and you're 100% responsible for what happens to them.
I feel like I agree with you to an extent, that it's definitely unfair to bring a child into this world and traumatize them by committing suicide if they are not yet capable of taking care of themselves. At the same time, I still feel bad for parents that thought they were doing a good thing in the beginning, only to have some unexpected circumstances leave them hurting badly enough to want to die, after the kids are alive. I think it depends entirely on the situation whether or not it's ethical, since not all situations are the same.
Committing suicide in a setting where the child will find you afterwards would definitely be a horrible thing, but perhaps if a suicidal parent can find a way for the child to be taken care of properly by someone else (friend or family member) that is more capable of giving them a good life, then perhaps that would alleviate some of the problems it might cause. It would just take careful planning to ensure that CTB impacts the child(ren) as little as possible, which might relieve the parent from the burden of this ethical problem.
And I don't care about the counterargument that having a depressed parent is worse than no parent at all. People should think about this before deciding to have children. The only correct course of action in this case is to learn to fake it and endure the rest of your life while trying to minimize the damage.
I feel like you got more harsh reactions than you probably should have about your stance on this argument (unfortunately you seem to have been accused of being against all counterarguments, rather than just this one), but with that being said, I'm still curious as to why you have rejected this as a valid argument. Maybe in some cases it doesn't work, but I would have to say that in my particular case, I wouldn't want any child to endure my parenting. That could be almost as traumatic as me committing suicide might be.
To be honest, if I was a parent and CTB, my kids would probably be like, "Finally! I'm glad he's gone!"

(I am joking here, so don't take that too seriously.)
I also want to ask why you think a parent should fake it for the rest of their life. Surely when the children have reached adulthood, it won't matter as much. Even if they are still young, wouldn't it be possible to minimize the damage without giving up suicide? It would take careful planning obviously, but there must be a way to do it. I feel like the backlash you have been receiving is because it seems like you think parents should be punished by staying alive until they die naturally. If you didn't intend for it to sound that way, then maybe it would be a good idea to clear up the misunderstanding?
Ok I'm sorry that I misunderstood you. I completely disagree with this and I think you constructed a false equivalence. Stealing during a famine is obviously not compared to having a kid when not completely sure you won't kill yourself at some point. It's ludicrous to say the ethical considerations are the same. For one, the damage caused by stealing is outweighed by the benefit of keeping people alive. It's logical and almost everyone would agree with this. On the other hand, I've made the case that the benefit of killing yourself does not outweigh the damage done in that circumstance.
I don't think the intent was to say that stealing during a famine was the same as committing suicide as a parent. It just looked like a good example of someone sacrificing their ethical standards to alleviate suffering. If someone is suffering too much for living to be worth it, then I can understand someone committing suicide, regardless of how it might affect others when they get to a point where they can't handle it anymore.