The toothpaste is out of the tube as far as masks. I don't know how you change that anti-mask attitude at this point. That is just one part of the problem though.
Pandemic fatigue is a real thing. There were signs of it a couple weeks into this thing, and here we are many months into it. I think it is exacerbated by modern society for various reasons.
You are not safe if you gather in a group of 4. Or even 3, or 2, if it happens to be the wrong person. Safer than a larger group, but not safe. It is a lot to ask people to give up all in person social interaction, but as long as it happens, it is a way to spread the virus especially if you're not wearing a mask.
As far as a vaccine, there is a lot of mistrust with that. In fact, this may end up being the least trusted vaccine that we have seen in a long time in this country. Even if we are optimistic and say the vaccine will be effective at a rate of 70-90%, the impact will only be so much if less than half of the country gets it.
Maybe we will see better treatments come out over time. Actually, I would expect that. But as far as putting an end to this pandemic, I don't really see it anytime soon, especially in the United States.