Go sailing. Learn how to carve wood. Make out with another human on a beach. Go take pictures in a foreign country. Learn how to play an instrument. Grow some vegetables. Volunteer in your local community. Go to a bookstore/library, pick a completely random fiction book, and force yourself to read it from cover to cover.
It gets better.
(I am experiencing a somewhat similar "phase" with codeshaman)
You gotta eat your vegetables.
(Damn, I sound so lost! :D)
P.S: Your comment on the Tinder topic a couple of days ago (https://news.ycombinator.com/item?id=10019527) was spot on, you really nailed it. Thanks for sharing all these thoughts.
You are right again, it's a self fulfilling prophecy - the more you dwell on it, the more pointless the whole thing becomes. But as sebkomianos said, it's like a vicious circle: In order to engage and find meaning I need to find meaning so I get inspired to engage.
The solution is, I guess, to pretend for a while and just do something and then it will start making sense again. I'm doing that, trying to produce sparks to ignite the fire, I'm almost there....