Think coordination. Two agents may coordinate their actions, if doing so will benefit both. In this sense, it's cooperation. It doesn't include fighting over preferences, fighting over preferences will just consist in them acting on environment without coordination. But this should never be possible, since the set of coordinated plans is strictly greater than a set of uncoordinated plans, and as a result it should always contain a solution that is a Pareto improvement on the best uncoordinated one, that is at least as good for both players as the best uncoordinated solution. Thus, it's always useful to coordinate your actions will all other agents (and at this point, you also need to dole the benefit of coordination to each side fairly, think Ultimatum game).
My girlfriend/SO's grandfather died last night, running on a treadmill when his heart gave out.
He wasn't signed up for cryonics, of course. She tried to convince him, and I tried myself a little the one time I met her grandparents.
"This didn't have to happen. Fucking religion."
That's what my girlfriend said.
I asked her if I could share that with you, and she said yes.
Just so that we're clear that all the wonderful emotional benefits of self-delusion come with a price, and the price isn't just to you.