I'm mostly a nihilist. I don't think there is any meaning in life. I don't think meaning has anything to do with ethics.

Ethics comprise a system of rules that evolves with society that are based on that particular community's survival. If, for instance, people in that society went around murdering each other, the society wouldn't last very long. Or if they all cheated and lied, the same thing would happen. Ethics are, essentially, a survival mechanism.

According to your interpretation, one wouldn't be ethical, yet I'm 70 years old, and there isn't a person in my life that wouldn't tell you I have an exceptional code of ethics. That's simply because I understand that the 'right' thing to do is not to harm others, because in harming others, one harms society, and the eventual outcome of this is extinction of the species.

In the long term, we will become extinct anyway, so I suppose it doesn't really matter if that happens sooner or later, but I do believe that some options are better than other options - not because life has any meaning - but because life may be valuable in ways we do not know.