1. We have each other.
2. Things can matter if you THINK they matter. There is no universal constant assigning worth to things, yeah. On a philosophical scale, nothing and nobody matters. It's all meaningless. But why does that matter? Why spend time thinking about it? It's like thinking that the universe is going to end eventually . It might be true, eventually it will all be dust. And .... so? Why even spend time thinking about it?
It's all about personally, consciously or not, assigning worth to things. Does "Superman" matter? Well, do you like Superman comics? If you do, then they matter to you. Hence Superman matters to someone, so Superman matters. And he even matters a lot more than that, considering there are millions of people who are Superman fans. So he matters quite a great deal.
3. Why do people bring this up as if it's important or significant in any way? You were born alone too, you realize that right? Does anyone give a shit about the fact that everyone was "born alone"? I really don't see the big deal about this one, I never have. As long as you have people who love you and that you love, you are not alone. And if you really are still bent up out of shape over it go jihad a bus, that way some people can die at the exact same point in time that you do. Because that apparently matters? No. It's such a non issue.
The point: meaning lies where men attribute meaning to lie. No more, no less.