[npinsker]

It sounds like you are depressed, and should figure out whether it's due to maladaptive biochemistry (see a professional) or circumstances (change the circumstances; maybe consider a therapist). Given your post, I'm leaning towards the latter.

You say you have plenty of friends, but I can't help but wonder if they're able to give you the nourishment you need. It's great you have many who care about you -- but no matter how much you go drinking or hiking together, if they can't relate to your troubles, then it can still feel quite lonely.

For me personally, art -- both creating and consuming others' -- has been uniquely helpful. You can pass your feelings to a future self, and there are surely many brilliant people from the past whose work can make you feel understood too. Yes, "this" really is all there is, but it's more manageable if you find someone who sees "this" the same way you do.

What's compelling about "starting from zero"? Maybe that's a feeling you could focus in on and, from that, figure out a goal that compels you.

Good luck. Hope you find happiness :)